feat: add telegram-cli web chat interface and /api/chat endpoint

- Add telegram-cli Worker with web chat UI for browser-based bot testing
- Add POST /api/chat authenticated endpoint (Bearer token, production enabled)
- Fix ENVIRONMENT to production in wrangler.toml (was blocking Service Binding)
- Add Service Binding (BOT_WORKER) for Worker-to-Worker communication
- Add cloud-db-schema.sql for local development

telegram-cli features:
- Web UI at GET / with dark theme
- JSON API at POST /api/chat
- Service Binding to telegram-summary-bot Worker

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

telegram-cli/.env.example

@@ -0,0 +1,10 @@
+# Telegram Bot Configuration
+BOT_TOKEN=your_telegram_bot_token_here
+WEBHOOK_SECRET=your_webhook_secret_here
+CHAT_ID=your_telegram_user_id_here
+
+# Worker Configuration
+WORKER_URL=https://telegram-summary-bot.kappa-d8e.workers.dev
+
+# Optional: Enable debug mode
+DEBUG=false