GRM-36: feat: implement documentation-as-code with wiki sync and doc-coverage

Add /docs/ directory with user and technical documentation extracted from README, AGENTS.md, and source code. Add scripts/sync_wiki.py to sync docs to Gitea wiki via API. Add scripts/doc_coverage.py to check CLI commands, modules, and CI scripts are documented. Add sync-wiki.yml workflow for auto-sync on merge and release. Slim down README.md to lean entry point. 28 new unit tests, 100% coverage maintained.

Closes GRM-36

.gitea/workflows/ci.yml

@@ -30,6 +30,10 @@ jobs:
         run: |
           . .venv/bin/activate
           PYTHONPATH=src python3 scripts/release.py --dry-run || true
+      - name: Documentation coverage check
+        run: |
+          . .venv/bin/activate
+          PYTHONPATH=src python3 scripts/doc_coverage.py
 
   detect-changes:
     runs-on: docker

.gitea/workflows/sync-wiki.yml

@@ -0,0 +1,31 @@
+name: Sync Wiki
+
+on:
+  push:
+    branches: [master]
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  sync-wiki:
+    runs-on: docker
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Set up environment
+        run: make setup
+      - name: Sync documentation to wiki
+        env:
+          REPO_TOKEN: ${{ secrets.REPO_TOKEN }}
+          PYTHONPATH: src
+        run: |
+          . .venv/bin/activate
+          python3 scripts/sync_wiki.py --repo "${{ github.repository }}"
+      - name: Tag wiki on release
+        if: startsWith(github.ref, 'refs/tags/v')
+        env:
+          REPO_TOKEN: ${{ secrets.REPO_TOKEN }}
+        run: |
+          echo "Release tag ${{ github.ref_name }} — wiki synced with release"