🔧 fix(docker): update Dockerfiles for monorepo-aware builds

- Update mana-search Dockerfile to use monorepo root context
- Update api-gateway Dockerfile to use monorepo root context
- Fix CI workflow to use context: . for mana-search
- Use pnpm --filter for proper workspace package installation

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -488,7 +488,7 @@ jobs:
           tags: type=raw,value=latest
       - uses: docker/build-push-action@v5
         with:
-          context: services/mana-search
+          context: .
           file: services/mana-search/Dockerfile
           platforms: linux/amd64,linux/arm64
           push: true