fix(ci): remove swagger from smoke test — disabled in production

Swagger (/swagger) is only enabled in Development mode (Program.cs
gates it behind app.Environment.IsDevelopment()). In production,
nginx serves the frontend catch-all (index.html), so the check
always returns 200 but never actually validates the API layer.

/health already covers API + database + runtime health checks.
No replacement endpoint needed — the smoke test still validates
both the dashboard and the backend API via /health.

.gitea/workflows/deploy.yaml

@@ -189,7 +189,7 @@ jobs:
       # ── Step 7: Smoke test (multi-endpoint) ───
       # Tests multiple endpoints to catch partial failures.
       # Why: a single /dashboard check can miss backend-only outages;
-      #   testing /api/swagger confirms the API layer is healthy too.
+      #   /health tests the API + database + runtime status.
       - name: Verify (smoke test)
         run: |
           echo "🔍 Smoke test..."
@@ -212,7 +212,6 @@ jobs:
 
           check "/dashboard" "Dashboard"    200
           check "/health"    "Health API"   200
-          check "/swagger"   "API Swagger"  200
 
           echo ""
           echo "Results: $PASS passed, $FAIL failed"