fix(discord): support least-privilege bot permissions without Administrator

[FaiThiX]

Summary

This PR removes the need to run the bot with Administrator and makes the Discord channel setup flow more reliable when using a minimal permission set.

The main issue was that the bot could create categories/channels and send messages, but it failed when applying channel/category permission overwrites. This PR updates the setup flow so the bot can safely work with explicit Discord permissions instead of relying on Administrator.

What Changed

• Added explicit bot permission overwrites so the bot does not lock itself out of its own channels.
• Created categories and text channels with their intended parent/overwrites during creation, instead of relying on a fragile create-then-fix flow.
• Updated channel parent handling to use await and lockPermissions: false to avoid overwrite conflicts during setup.
• Added recovery logic for stored channel IDs that exist but are no longer usable by the bot.
• Improved setup logging so permission-related failures are now visible at the exact API call that failed.

Why

The previous setup could fail in partially configured guilds because:

• the bot was able to create channels,
• but failed when updating permission overwrites,
• and in some cases could also end up with broken parent/permission sync behavior.

With this change, the bot now works correctly with a proper minimal permission set and no longer requires Administrator.

Required Bot Scopes

• bot
• applications.commands

Required Bot Permissions

These permissions are required for normal full operation with the current codebase:

• View Channels
• Manage Channels
• Manage Roles
• Send Messages
• Embed Links
• Attach Files
• Read Message History
• Manage Messages

Optional Bot Permissions

These are only needed if the related features are used:

• Mention Everyone
  Required for @everyone / @here notification features.
• Change Nickname
  Required if the bot should set/update its server nickname on startup.
• Connect
  Required for voice channel features.
• Speak
  Required for voice playback features.
• Send TTS Messages
  Required for Discord TTS output.

Not Required

The bot does not require:

• Administrator
• Kick Members
• Ban Members
• Manage Webhooks
• Manage Guild
• thread permissions
• moderation/timeouts permissions

Result

The bot can now be installed with a least-privilege permission model while still supporting channel creation, overwrite management, embeds, attachments, and normal setup automation.