REFACTOR(repo): simplify project structure

- Move services/nextjs to nextjs/
- Move deploy/docker/Dockerfile.prod to Dockerfile
- Add GitHub Actions workflows (ci.yml, build.yml)
- Remove deploy/, services/, scripts/ folders

.gitignore

@@ -0,0 +1,56 @@
+# dependencies
+node_modules
+services/nextjs/node_modules
+.pnp
+.pnp.*
+
+# testing
+coverage
+
+# next.js
+services/nextjs/.next/
+.next/
+/out/
+
+# production
+/build
+
+# misc
+.DS_Store
+*.pem
+
+# debug
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.pnpm-debug.log*
+
+# env files
+.env*
+!.env.example
+
+# vercel
+.vercel
+
+# typescript
+*.tsbuildinfo
+next-env.d.ts
+
+# prisma
+/prisma/dev.db
+/prisma/dev.db-journal
+/prisma/*.db
+/prisma/*.db-journal
+
+# IDE
+.vscode
+.idea
+*.swp
+*.swo
+*~
+
+# OS
+Thumbs.db
+
+# trunk
+.trunk