ci: run frontend-deps and frontend-build in parallel, both gate QC

frontend-deps (dep staleness check) and frontend-build now run concurrently. frontend-qc waits for both. Removed (gate) from build job name.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

.gitea/workflows/ci.yaml

@@ -326,8 +326,7 @@ jobs:
           "
 
   frontend-build:
-    name: Frontend build (gate)
-    needs: [frontend-deps]
+    name: Frontend build
     runs-on: ubuntu-latest
     defaults:
       run:
@@ -358,7 +357,7 @@ jobs:
 
   frontend-qc:
     name: Frontend QC (${{ matrix.task }})
-    needs: [frontend-build]
+    needs: [frontend-deps, frontend-build]
     runs-on: ubuntu-latest
     defaults:
       run: