REFACTOR(repo): simplify project structure

- Move services/nextjs/ to nextjs/
- Move Dockerfile.prod to Dockerfile at root
- Remove deploy/ folder (K8s manifests moved to K3S-HOME/web-apps)
- Remove .gitea/ workflows
- Update GitHub Actions for new structure
- Remove develop branch triggers

nextjs/.eslintrc.json

@@ -0,0 +1,3 @@
+{
+  "extends": "next/core-web-vitals"
+}