Initial commit: EGBE chatbot template

Stripped from vercel/chatbot (Apache 2.0):
- Dropped @vercel/* packages and AI Gateway
- Removed artifacts feature (code/text/sheet/image side panel)
- Switched AI provider to @ai-sdk/openai-compatible -> EGBE LiteLLM
- Replaced Vercel Blob upload with data URLs
- Dropped Redis resumable streams and rate limiter (in-memory now)
- Added Dockerfile (Next.js standalone) + entrypoint that runs migrations
- Wired DATABASE_URL, EGBE_AI_API_URL/KEY, NEXT_PUBLIC_BASE_URL for app-deploy.sh

.gitignore

@@ -0,0 +1,27 @@
+node_modules
+.pnp
+.pnp.js
+coverage
+.next/
+out/
+build
+.DS_Store
+*.pem
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+.pnpm-debug.log*
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+.turbo
+.env
+.vercel
+.env*.local
+/test-results/
+/playwright-report/
+/blob-report/
+/playwright/*
+next-env.d.ts
+tsconfig.tsbuildinfo