ci: fix nginx http.d dir, golangci-lint timeout, frontend major deps parallel

- nginx-check: Alpine's nginx package includes /etc/nginx/conf.d at
  MAIN level and /etc/nginx/http.d at HTTP level. Use http.d so that
  proxy_cache_path, limit_req_zone, and server blocks are valid.
- golangci-lint: add --timeout 5m to prevent timeout on first run
  when Go module cache is cold and many deps must be downloaded
- frontend-deps-major: remove needs dependency so it runs in parallel
  with frontend-deps (provides visibility even when deps check fails)

.gitea/workflows/ci.yaml

@@ -194,7 +194,7 @@ jobs:
       - name: golangci-lint
         run: |
           go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest
-          golangci-lint run ./...
+          golangci-lint run ./... --timeout 5m
         working-directory: backend
 
   go-staticcheck-dev:
@@ -666,8 +666,7 @@ jobs:
           "
 
   frontend-deps-major:
-    name: Frontend major deps (warn only)
-    needs: [frontend-deps]
+    name: Frontend major deps
     runs-on: ubuntu-latest
     defaults:
       run:
@@ -911,6 +910,6 @@ jobs:
 
       - name: Validate nginx config
         run: |
-          mkdir -p /etc/nginx/conf.d
-          cp $(pwd)/nginx/conf.d/default.conf /etc/nginx/conf.d/default.conf
+          mkdir -p /etc/nginx/http.d
+          cp $(pwd)/nginx/conf.d/default.conf /etc/nginx/http.d/default.conf
           nginx -t