Own app id com.codedeck.plus + plus-badged icon

[deymosh]

Why

The Android identifier was still com.codedeck.next — identical to upstream CodeDeck Next. Consequences:

• Can't install CodeDeck+ alongside upstream (same package name).
• Can't install it over upstream either — different signing key → INSTALL_FAILED_UPDATE_INCOMPATIBLE.
• The README claimed "installs side by side", which was untrue.

v0.10.0 has ~0 real installs, so this is the moment to fix it.

App id → com.codedeck.plus

Distinct from both the original CodeDeck (com.codedeck.app) and upstream CodeDeck Next (com.codedeck.next):

• tauri.conf.json identifier; gen/android/app/build.gradle.kts namespace + applicationId; MainActivity.kt package + its directory (git mv); the buildSrc Kotlin directory (git mv); gen/android/app/.gitignore generated-sources path.
• strings.xml app_name / main_activity_title were still "CodeDeck Next" → "CodeDeck+" (this is the launcher label under the icon).
• MeshSection.tsx WD_GRANT_CMD (a real adb pm grant string) and a stale tauri-plugin-mesh manifest comment (it had com.codedeck.app).
• apps/mobile/README.md reworded to explain the three-way coexistence.
• Removed apps/mobile/zapstore.yaml — upstream's Zapstore publish config (their repo, app id, signing identity, a docs/RELEASE.md we don't ship). Nothing in the tree reads it.

RELEASE_NOTES_0.9.{0,3}.md keep their com.codedeck.next mentions — accurate history of upstream's releases.

Icon

The top ring's inner dot now carries a white "+", centred on the dot's true centroid (found by erosion, since dot and ring share a colour). Regenerated every size with tauri icon; kept the existing legacy-PNG icon scheme — dropped the desktop .icns/.ico/Square*, the ios/ set, and the mipmap-anydpi-v26 adaptive-icon files that tauri icon also emits (adaptive icons would be a separate change).

Verification

• Docker APK build (./codedeck apk debug) — compiles clean.
• aapt2 dump badging on the built APK:
  • package: name='com.codedeck.plus'
  • application-label:'CodeDeck+'
  • launchable-activity: name='com.codedeck.plus.MainActivity'
  • icons resolve to res/mipmap-*/ic_launcher.png
• ./codedeck check — typecheck + 765 mobile tests + the rest, green.

Ships in the next release (v0.11.0 — new app id is a user-visible identity change; worth a RELEASE_NOTES entry).

Note for later (out of scope): bundle.android.versionCode is pinned at 6 in tauri.conf.json, so the APK's versionCode doesn't track version — fine for a fresh app id, but worth revisiting.