Refactor to apps/ structure

JIGAIDO is now a platform with apps/ as the container.
All telegram-bot files moved to apps/telegram-bot/:
- bot.py, commands.py, cron.py, db.py, schema.sql
- requirements.txt, .env.example, README.md
- Root now holds SPEC.md, README.md, CONTRIBUTING.md only.

Structure:
jigaido/
├── apps/
│   └── telegram-bot/
└── SPEC.md, README.md, CONTRIBUTING.md

SPEC.md

@@ -31,14 +31,17 @@ JIGAIDO is a Telegram bot that lets groups and individuals track bounties — ta
 
 ```
 jigaido/
-├── bot.py           # Telegram bot entrypoint, command handlers
-├── db.py            # SQLite wrapper
-├── schema.sql       # Database schema
-├── cron.py          # Daily reminder job
-├── requirements.txt
-├── .gitignore
-├── README.md
+├── apps/
+│   └── telegram-bot/     # Telegram bot app
+│       ├── bot.py       # Entrypoint
+│       ├── commands.py  # Command handlers
+│       ├── cron.py      # Daily reminder job
+│       ├── db.py        # SQLite wrapper
+│       ├── schema.sql   # Database schema
+│       ├── requirements.txt
+│       └── .env.example
 ├── SPEC.md          # This document
+├── README.md
 └── CONTRIBUTING.md
 ```