Gracefully handle errors when unbanning users

[SitiSchu]

Currently the bot will simply refuse to unban a person if it fails to unban them in any of the groups.
Some cases where this can happen:

1. Bot was in a group that is now deleted, but the group is still in the DB
   • Need to manually edit the DB to remove the group
2. Group doesn't have the rights to unban the user in a group
   • For example the private moderation group where theres no point in banning users

Preferably the bot would just skip over these issues and still unban the user instead of making it impossible to unban them (and it also being impossible to know why its not working since theres no message from the bot, just a log on the server).
It should probably also remove inaccessible groups from its DB.

Example for 2.

TelegramError: 400: Bad Request: not enough rights to restrict/unrestrict chat member
    at Telegram.callApi (/app/node_modules/telegraf/lib/core/network/client.js:315:19)
    at processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async Promise.all (index 0)
    at async unbanHandler (/app/handlers/commands/unban.js:39:2)
    at async execute (/app/node_modules/telegraf/lib/composer.js:518:17)
    at async /app/node_modules/telegraf/lib/composer.js:519:21
    at async execute (/app/node_modules/telegraf/lib/composer.js:518:17)
    at async /app/node_modules/telegraf/lib/composer.js:519:21
    at async execute (/app/node_modules/telegraf/lib/composer.js:518:17)
    at async /app/node_modules/telegraf/lib/composer.js:519:21 {
  response: {
    ok: false,
    error_code: 400,
    description: 'Bad Request: not enough rights to restrict/unrestrict chat member'
  },
  on: {
    method: 'unbanChatMember',
    payload: { chat_id: -100xxxxxxxxxx, user_id: 81xxxxxx }
  }
}

[MKRhere]

Maybe we want to respond with an error that it was unsuccessful in some groups? And I suppose we could add a /leave [chat_id] optional parameter.

[SitiSchu]

For the case of the inaccessible group it makes sense to respond with an error yeah.
For the case with missing permissions it'd get old real quick to constantly be reminded, but I'm not sure what the best way to handle it would be. Can probably just ignore it and write a log warning, the user will usually notice when they're unbanned but still can't join some groups.

Perhaps if you want to be super fancy a /health command of sorts could be added that checks permissions in each group and writes a nicely formatted message. No idea if the TG API supports this though.