Telegram Notification Bot Development

I need a Telegram bot whose main job is to push timely notifications to our users. Users will authenticate exclusively through Telegram login, so the bot must request and validate each user’s Telegram credential before any interaction.

Beyond simply sending messages, the bot should:
• Parse incoming messages so I can trigger different notification flows based on keywords or commands.
• Store and retrieve data through a lightweight database layer—feel free to use SQLite, Postgres, or MongoDB as long as setup remains straightforward.
• Maintain clean, well-documented code and a brief README that shows how to deploy the bot, add new notification templates, and connect the database.

Reliability is important: messages must reach the intended recipients without duplication, and errors should be logged clearly. You’re welcome to build in Python (aiogram or python-telegram-bot) or Node.js (Telegraf) if that speeds development, but I’m open to other stacks as long as they are well-supported.

Please include:
1. The complete, runnable source code.
2. A step-by-step setup guide that covers bot token creation and database initialization.
3. Simple instructions for adding future features such as extra parsing rules or additional authentication checks.

If you have previous Telegram bot examples or can outline how you’ll handle authentication and database integration, that will help me decide quickly.