Fix: git in Docker builder (page dates) + serve raw .md as text/markdown

Dockerfile

@@ -6,6 +6,14 @@ ENV NODE_OPTIONS=--max_old_space_size=16000
 
 WORKDIR /app
 
+# Docusaurus derives per-page dates from git history: sitemap <lastmod>,
+# the "Last updated" footer (showLastUpdateTime/Author), and the
+# TechArticle JSON-LD dates. node:20-alpine ships without git, so these are
+# silently dropped from production builds unless git is installed here.
+# NOTE: the build context must include the .git directory (do not add .git to
+# .dockerignore) and the checkout must not be shallow, or dates will be partial.
+RUN apk add --no-cache git
+
 COPY . .
 
 RUN yarn install && yarn build

nginx/default.conf

@@ -52,6 +52,16 @@ server {
         add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;
     }
 
+    # Raw markdown twins (/docs/**/index.md) emitted by plugins/llms-txt.js for
+    # LLM/agent consumption. nginx has no mime type for .md, so they were served
+    # as application/octet-stream — browsers download them instead of displaying,
+    # and some crawlers skip non-text types.
+    location ~ \.md$ {
+        default_type text/markdown;
+        charset utf-8;
+        add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;
+    }
+
     # Doc images/videos are updated in place — cache hard but allow revalidation
     location /img/ {
         try_files $uri =404;