feat(fable-mcp): build wheel in Docker image, serve download, add admin log tool, and Settings install UI

- Dockerfile: build fable-mcp wheel into /app/dist/ during image build
- routes/fable_mcp_dist.py: GET /api/fable-mcp/info + /download endpoints
- app.py: register fable_mcp_dist_bp
- fable_mcp/tools/admin.py: get_app_logs() hitting /api/admin/logs
- fable_mcp/server.py: fable_get_app_logs MCP tool
- SettingsView: "Fable MCP" section in API Keys tab with download button and install instructions
- client.ts: getFableMcpInfo() helper
- ci.yml: add fable-mcp/** to trigger paths

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.forgejo/workflows/ci.yml

@@ -26,6 +26,7 @@ on:
       - "alembic.ini"
       - "Dockerfile"
       - "assets/**"
+      - "fable-mcp/**"
       - ".forgejo/workflows/ci.yml"
   # pull_request trigger intentionally omitted — all changes go through dev
   # first, where CI already runs on push. PR runs would be redundant duplication.