feat(lessons): add Claude Code Workshop lesson (12), adapted from workshops-de/workshop-claude-code

Ports all 27 tasks from https://github.com/workshops-de/workshop-claude-code 1:1 in structure
(stepped 010-270 numbering, categories, timing, no prepared repository/solution branches --
participants own every line, same as the source workshop).

Reference domain adapted from the source's 'pawsaw/clash' (Next.js monolith + Prisma) to a new
'Bookmonkey Community' brief (users lend/borrow books, request/accept/reject workflow) built on
this course's actual stack (Next.js frontend + PHP/Slim backend + SQLite via PDO) -- inspiration
only, not starter code, mirroring the source's own philosophy.

7 of 27 tasks required real architecture rewrites (not just renaming) because the source assumes
a Next.js-only monolith with Prisma/Server Actions, while this course uses a split frontend/
backend:
- 060-project-initialization: scaffold both a Next.js frontend AND a separate PHP/Slim backend
- 070-domain-modelling: brief changed to the book-lending domain
- 080-database-design: Prisma schema/migrate/seed -> raw schema.sql + PDO migrate.php/seed.php,
  with SQLite-specific pitfalls (foreign keys off by default, no native enums) replacing the
  Prisma 7.x pitfalls
- 090-authentication: Next.js Server Actions + jose/cookies -> PHP endpoints issuing a signed
  token, consumed by a Next.js Route Handler/guard
- 100-ui-development: server components + Server Actions -> frontend fetch/mutate against a PHP
  REST API, validated on both sides for different reasons (UX vs. security)
- 110-maps: entity types (clashes/venues) -> books/bookstores
- 120-participation-and-notifications: join/accept/reject -> borrow-request accept/reject

The remaining 20 tasks are Claude Code tool mechanics (installation, permission modes, CLAUDE.md,
context engineering, skills, commands, subagents, hooks, MCP, refactoring, debugging, TDD,
headless automation, code review, autonomous workflows, Agent SDK, alternative models, Spec Kit,
BMAD) and needed only light touch-ups (renaming the example domain in passing mentions).

Slides intentionally not authored yet (per explicit scope decision) -- lesson.yml has a TODO and
this lesson is not yet linked from 00-index.md/slides.md to avoid referencing a non-existent
Slidev entry file.

Author: robinboehm

README.md

@@ -69,9 +69,27 @@ Details siehe [`app/README.md`](./app/README.md).
 | 09  | Model Context Protocol        | MCP-Server generiert React-Komponenten & PHP-Controller statt Angular-Code       |
 | 10  | Agentic Workflow               | unverändert (stack-agnostisch, GitHub Actions)                                 |
 | 11  | Evals                          | unverändert (Tool ist stack-agnostisch)                                        |
+| 12  | Claude Code Workshop           | adaptiert von [`workshop-claude-code`](https://github.com/workshops-de/workshop-claude-code) (27 Tasks, gleiches Nummernschema); Referenz-Domäne "Bookmonkey Community" (Bücher ausleihen) statt "Clash"; **Slides fehlen noch** (siehe `lesson.yml`) |
 
 Details zur Migrationsentscheidung: siehe Konzept-Zusammenfassung im PR/Commit-Verlauf.
 
+### Lesson 12: Claude Code Workshop
+
+Diese Lesson ist strukturell 1:1 von [`workshop-claude-code`](https://github.com/workshops-de/workshop-claude-code)
+übernommen (27 Tasks, gestuftes Nummernschema `010`–`270`, keine vorbereiteten Solution-Branches —
+Teilnehmer besitzen jeden Code, den sie schreiben, wie im Original). Referenz-App ist nicht
+[`pawsaw/clash`](https://github.com/pawsaw/clash), sondern eine erweiterte **"Bookmonkey
+Community"**-Domäne (Bücher ausleihen: Nutzer bieten Bücher zum Verleih an, andere fragen an, der
+Besitzer akzeptiert/lehnt ab) auf Next.js + PHP/Slim + SQLite — analog zu unserem `app/`-Ordner,
+aber bewusst **kein Startcode**: Teilnehmer bauen alles selbst auf.
+
+7 der 27 Tasks (`060`–`120`, "Building Bookmonkey") enthalten echte Architektur-Anpassungen
+gegenüber dem Original (Next.js-Monolith mit Prisma/Server-Actions → getrennte Next.js-Frontend +
+PHP/Slim-Backend-Architektur mit PDO/SQLite). Die restlichen 20 Tasks sind Claude-Code-Tool-Wissen
+und praktisch stack-agnostisch, daher nahezu unverändert übernommen.
+
+**Offen:** Die Slides (Google Slides im Original) fehlen noch für diese Lesson.
+
 ## 🔗 Platform Integration
 
 - **lesson.yml**: Lesson-Metadaten, werden zur workshops.de-Plattform synchronisiert

lessons/12-claude-code-workshop/lesson.yml

@@ -0,0 +1,33 @@
+# Lesson configuration for repository import
+# This file defines the lesson metadata that will be synced to the platform
+#
+# Adapted from https://github.com/workshops-de/workshop-claude-code (27 tasks, structure and
+# task-numbering scheme kept 1:1). No prepared repository/solution branch on purpose: like the
+# source workshop, participants own every line of code they write. The Bookmonkey app in this
+# repo's app/ folder is domain inspiration only (analogous to pawsaw/clash in the source
+# workshop), not starter code.
+
+name: 'AI React PHP: Claude Code Workshop'
+position: 11
+
+# Trainer (use email or slug to match existing trainer)
+# TODO: replace with the actual trainer email before going live
+trainer: trainer@workshops.de
+
+# No git integration: there is no prepared repository or solution branch (see above).
+
+# Presentation type: "google_slides" or "slidev"
+# TODO: slides not built yet - see AskQuestion decision "no_slides_yet". Fill in once authored,
+# either as a new Slidev deck (consistent with the rest of this repo) or a dedicated Google Slides
+# deck.
+slides_type: slidev
+
+# PDF sync (works for both Google Slides and Slidev)
+pdf_generation_enabled: true
+
+# Playground options
+stackblitz_enabled: false
+codesandbox_enabled: false
+
+# Status
+deprecated: false

lessons/12-claude-code-workshop/tasks/010-install-claude-code/body.md

@@ -0,0 +1,60 @@
+## Overview
+
+Before touching any code, get Claude Code installed as a terminal tool on your own machine and
+confirm it actually works end to end: it runs, you're signed in, and it responds. This is a pure
+setup task — no exploration, no code, just a working install you can rely on for the rest of the
+workshop.
+
+## Prerequisites
+
+- Node.js 18+ installed (`node -v`), if you plan to install via npm
+- A terminal you're comfortable in
+- A Claude account (Claude.ai or Claude Console)
+
+## Steps
+
+1. Install Claude Code using either method:
+
+   ```bash
+   # macOS / Linux / WSL — native install script
+   curl -fsSL https://claude.ai/install.sh | bash
+
+   # or via npm (any OS with Node.js 18+)
+   npm install -g @anthropic-ai/claude-code
+   ```
+
+2. Confirm it's on your `PATH` and check the version:
+
+   ```bash
+   claude --version
+   ```
+
+3. Navigate into any project directory and start a session:
+
+   ```bash
+   cd your-project
+   claude
+   ```
+
+4. **Sign in** when prompted (via Claude.ai or Claude Console) and wait for the prompt to become
+   interactive.
+
+5. **Test that it works**: ask a trivial question (for example, "what files are in this
+   directory?") and confirm you get a sensible response.
+
+6. Exit cleanly (`/exit` or `Ctrl+C`) and start it again to confirm the second launch is just as
+   smooth — no repeated login, no errors.
+
+## Success Criteria
+
+- [ ] `claude --version` runs without error
+- [ ] You are signed in to a Claude account
+- [ ] `claude` starts an interactive session in a project directory
+- [ ] The agent answered a trivial question about the current directory
+- [ ] Restarting the session does not require signing in again
+
+## References
+
+- Claude Code — Overview: https://code.claude.com/docs/en/overview
+- Claude Code — Quickstart: https://code.claude.com/docs/en/quickstart
+- Claude Code — CLI reference: https://code.claude.com/docs/en/cli-reference

lessons/12-claude-code-workshop/tasks/010-install-claude-code/hint.md

@@ -0,0 +1,23 @@
+<details>
+<summary>💡 Hint 1: "claude: command not found"</summary>
+
+Restart your shell (or open a new terminal tab) after installing — the `PATH` update often only
+takes effect in new shell sessions.
+
+</details>
+
+<details>
+<summary>💡 Hint 2: npm install permission errors</summary>
+
+If `npm install -g` fails with permission errors, prefer the native `curl` install script instead
+of reaching for `sudo`.
+
+</details>
+
+<details>
+<summary>💡 Hint 3: Stuck on sign-in</summary>
+
+Sign-in opens a browser window — if you're on a restricted or headless machine, check the docs for
+alternative authentication flows before assuming it's broken.
+
+</details>

lessons/12-claude-code-workshop/tasks/010-install-claude-code/task.yml

@@ -0,0 +1,14 @@
+# Task Configuration
+title: 'Install Claude Code and Verify It Works'
+position: 10
+category: 'Foundations'
+preparation: true
+estimated_time_in_minutes: 15
+always_unlocked: true
+
+# No git integration: there is no prepared repository or solution branch.
+
+# Note: Markdown content is loaded from separate files:
+# - body.md           -> Main task description
+# - hint.md           -> Hints for solving the task
+# - trainer_hint.md   -> Notes for trainers (not shown to participants)

lessons/12-claude-code-workshop/tasks/010-install-claude-code/trainer_hint.md

@@ -0,0 +1,21 @@
+## Learning goals
+
+- **Skills:** installing Claude Code; verifying an install end to end; basic troubleshooting.
+- **Concepts:** the CLI as a terminal-native tool; sign-in/session persistence.
+- **Takeaways:** a verified install now prevents lost time in every later task.
+
+## Facilitation notes
+
+- This is intentionally a **pure setup task**, split out from "Claude Code Fundamentals" so
+  installation problems don't eat into time meant for learning the tool itself.
+- Strongly recommend sending the prerequisites (Node.js version, account signup) to participants
+  **before** the session so this task takes minutes, not most of the first block.
+- Common blockers: outdated Node.js, corporate proxies/firewalls blocking the install script or
+  sign-in, and missing `PATH` updates after install. Have a fallback (e.g. a pre-provisioned
+  Codespace/devcontainer) ready for anyone who can't get unblocked quickly.
+- Walk the room and confirm every participant's `claude --version` succeeds before moving on to
+  the Fundamentals task — a broken install here compounds for the rest of the day.
+
+## Time estimate
+
+~15 minutes for most participants; corporate network restrictions can extend this significantly.

lessons/12-claude-code-workshop/tasks/015-workshop-api-key/body.md

@@ -0,0 +1,45 @@
+## Overview
+
+Point Claude Code at the API key provided for this workshop instead of your personal Claude
+account, using the built-in `/config` command. This keeps everyone's usage and cost on the
+workshop's shared billing and removes one more blocker before the first real exercise.
+
+## Prerequisites
+
+- Claude Code installed and verified (previous task)
+- The API key shared by your trainer for this workshop
+
+## Steps
+
+1. Get the workshop API key from your trainer (usually shared at the start of the session, e.g.
+   via chat or a slide).
+2. Start a session in any directory:
+
+   ```bash
+   claude
+   ```
+
+3. Open the configuration menu:
+
+   ```
+   /config
+   ```
+
+4. Find the API key / authentication setting and **paste in the workshop key**, then confirm/save.
+5. Restart `claude` (or open a fresh session) and confirm it does **not** prompt you to sign in
+   with a personal Claude.ai/Console account — it should use the configured key automatically.
+6. Ask a trivial question (for example, "what is 2 + 2") to confirm requests go through
+   successfully using the workshop key.
+
+## Success Criteria
+
+- [ ] `/config` shows the workshop API key as the active authentication method
+- [ ] Starting `claude` does not prompt for personal sign-in
+- [ ] A trivial question was answered successfully using the workshop key
+- [ ] The setting persists in a freshly opened session without repeating `/config`
+
+## References
+
+- Claude Code — Slash commands: https://code.claude.com/docs/en/slash-commands
+- Claude Code — Settings: https://code.claude.com/docs/en/settings
+- Claude Code — Overview: https://code.claude.com/docs/en/overview

lessons/12-claude-code-workshop/tasks/015-workshop-api-key/hint.md

@@ -0,0 +1,23 @@
+<details>
+<summary>💡 Hint 1: Still being asked to log in?</summary>
+
+Check for a leftover personal login session — it can take priority over the key set via
+`/config`. Sign out of any personal account first if you're unsure which one is active.
+
+</details>
+
+<details>
+<summary>💡 Hint 2: Can't find the API key option in /config</summary>
+
+`/config` opens a menu — look for an authentication or API key entry specifically; don't confuse
+it with unrelated settings like theme or permissions.
+
+</details>
+
+<details>
+<summary>💡 Hint 3: Never paste the key elsewhere</summary>
+
+Only paste the key into the `/config` prompt itself — never into a file you might commit to git
+or share in chat outside the intended channel.
+
+</details>

lessons/12-claude-code-workshop/tasks/015-workshop-api-key/task.yml

@@ -0,0 +1,14 @@
+# Task Configuration
+title: 'Set Up the Workshop API Key'
+position: 15
+category: 'Foundations'
+preparation: false
+estimated_time_in_minutes: 10
+always_unlocked: false
+
+# No git integration: there is no prepared repository or solution branch.
+
+# Note: Markdown content is loaded from separate files:
+# - body.md           -> Main task description
+# - hint.md           -> Hints for solving the task
+# - trainer_hint.md   -> Notes for trainers (not shown to participants)

lessons/12-claude-code-workshop/tasks/015-workshop-api-key/trainer_hint.md

@@ -0,0 +1,22 @@
+## Learning goals
+
+- **Skills:** configuring authentication via the `/config` command.
+- **Concepts:** API key vs. personal account auth; shared workshop billing.
+- **Takeaways:** the workshop key removes a sign-up blocker so everyone can start together.
+
+## Facilitation notes
+
+- **Deliberately locked and not marked as preparation**: the key should only be handed out live,
+  at the start of the session (not before), so unlock this task yourself once you've shared the
+  key with the room.
+- Share the key in a way participants can copy-paste reliably (chat message or a slide with
+  copyable text) — reading it aloud invites typos.
+- Walk through `/config` once on your own machine beforehand so you can point participants to the
+  exact menu entry live instead of hunting for it together.
+- Keep an eye on usage/cost during the workshop; consider rotating or revoking the key afterwards.
+- If a participant already has a personal Claude account logged in, help them confirm the
+  workshop key is actually the one being used (the personal login can otherwise take precedence).
+
+## Time estimate
+
+~10 minutes once the key has been shared.