fix: reliable source upload, build cancel, WordPress port 80 default

- Replace port-forward/netcat PVC upload with kubectl cp for integrity
- Add build cancellation API and session cleanup; deploy catches cancel
- Default port 80 for WordPress, PHP, and Laravel on create
- Build progress modal with cancel; Helm/K8s adjustments for deployments
- Update build and kubernetes specs

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/helm/cloudhost-app/values.yaml

@@ -51,7 +51,6 @@ database:
 # ── WordPress-specific ───────────────────────────────────
 wordpress:
   enabled: false
-  wpContentStorageSize: "2Gi"
 
 # ── Redis ──────────────────────────────────────────────
 redis: