feat: live Gitea changelog, Gitea sidebar link, release title/body extraction

- Admin changelog page now fetches releases live from the public Gitea
  API (https://gitea.kalekber.cc) instead of a baked releases.json file
- Remove /static/releases.json from ui/.gitignore (no longer generated)
- Add Gitea to admin sidebar external tools (admin_nav_gitea i18n key,
  all 5 locales, compiled paraglide JS force-added)
- release.yaml: remove 'Fetch releases from Gitea API' step; extract
  release title and body from the tagged commit message for Gitea releases

.gitea/workflows/release.yaml

@@ -190,17 +190,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Fetch releases from Gitea API
-        run: |
-          set -euo pipefail
-          RESPONSE=$(curl -sfL \
-            -H "Accept: application/json" \
-            "http://gitea.kalekber.cc/api/v1/repos/kamil/libnovel/releases?limit=50&page=1")
-          # Validate JSON before writing — fails hard if response is not a JSON array
-          COUNT=$(echo "$RESPONSE" | jq 'if type == "array" then length else error("expected array, got \(type)") end')
-          echo "$RESPONSE" > ui/static/releases.json
-          echo "Fetched $COUNT releases"
-
       - uses: docker/setup-buildx-action@v3
 
       - name: Log in to Docker Hub
@@ -278,8 +267,25 @@ jobs:
         with:
           fetch-depth: 0
 
+      - name: Extract release notes from tag commit
+        id: notes
+        run: |
+          set -euo pipefail
+          # Subject line (first line of commit message) → release title
+          SUBJECT=$(git log -1 --format="%s" "${{ gitea.sha }}")
+          # Body (everything after the blank line) → release body
+          BODY=$(git log -1 --format="%b" "${{ gitea.sha }}" | sed '/^Co-Authored-By:/d' | sed '/^[[:space:]]*$/{ N; /^\n$/d }' | sed 's/^[[:space:]]*$//' | awk 'NF || !p; {p = !NF}')
+          echo "title=${SUBJECT}" >> "$GITHUB_OUTPUT"
+          # Use a heredoc delimiter to safely handle multi-line body
+          {
+            echo "body<<RELEASE_BODY_EOF"
+            echo "${BODY}"
+            echo "RELEASE_BODY_EOF"
+          } >> "$GITHUB_OUTPUT"
+
       - name: Create release
         uses: https://gitea.com/actions/gitea-release-action@v1
         with:
           token: ${{ secrets.GITEA_TOKEN }}
-          generate_release_notes: true
+          title: ${{ steps.notes.outputs.title }}
+          body: ${{ steps.notes.outputs.body }}