feat: support multiple Telegram allowlisted users

[musichen]

Summary

Allow the Telegram bridge to authorize multiple Telegram accounts while keeping existing single-account configurations working.

What changed

• Add allowedUserIds as the canonical allowlist setting.
• Accept messages from any user ID in the list.
• Migrate the existing allowedUserId setting to allowedUserIds when the configuration is read.
• Update pairing, status reporting, and documentation for multiple accounts.

Configuration

"allowedUserIds": [530236679, 123456789]

Existing configurations using allowedUserId are migrated automatically.

Testing

Verified the TypeScript changes by inspection and validated the JSON configuration format.

[musichen]

@badlogic
One compatibility note: existing configurations using the single-user setting

"allowedUserId": 530236679

continue to work. On the next bridge reconnect, the setting is migrated automatically to:

"allowedUserIds": [530236679]

This preserves the existing authorized account while allowing additional IDs to be added.