feat: turbostarter boilerplate

Production-ready Next.js boilerplate with:
- Runtime env validation (fail-fast on missing vars)
- Feature-gated config (S3, Stripe, email, OAuth)
- Docker + Coolify deployment pipeline
- PostgreSQL + pgvector, MinIO S3, Better Auth
- TypeScript strict mode (no ignoreBuildErrors)
- i18n (en/es), AI modules, billing, monitoring

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.dockerignore

@@ -0,0 +1,37 @@
+# Build outputs
+.next
+.turbo
+dist
+out
+.expo
+.wxt
+
+# Dependencies (will be installed fresh in Docker)
+node_modules
+**/node_modules
+.pnpm-store
+
+# Development
+.git
+.gitignore
+*.md
+*.log
+npm-debug.log
+
+# IDE
+.vscode
+.idea
+
+# Test
+coverage
+.nyc_output
+
+# Docker
+Dockerfile
+.dockerignore
+
+# Misc
+.DS_Store
+*.local
+.env*.local
+tmp/