ci: inline DATABASE_URL in workflow (volcano RDS internal endpoint)

Matches the AirGate convention of putting infra credentials directly in
the deploy yaml — no Gitea Secrets configuration required, push-to-deploy
just works.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitea/workflows/deploy.yaml

@@ -93,9 +93,9 @@ jobs:
                 --docker-password="${{ env.CR_PASSWORD_ACTIVE }}" \
                 --dry-run=client -o yaml | kubectl apply -f -
 
-              # 2) 应用运行时 Secret（数据库连接串）
+              # 2) 应用运行时 Secret（数据库连接串：火山 RDS 内网地址）
               kubectl create secret generic cyberstar-env \
-                --from-literal=DATABASE_URL='${{ secrets.DATABASE_URL }}' \
+                --from-literal=DATABASE_URL='mysql://zyc:Zyc188208@mysql8351f937d637.rds.ivolces.com:3306/cyberstar?charset=utf8mb4' \
                 --dry-run=client -o yaml | kubectl apply -f -
 
               # 3) Apply manifests