Add discord webhook support

[tsIsFried]

Description

Adds Discord webhook support to py-clash-bot, allowing users to receive real-time notifications about bot activity directly in Discord.

Changes Made

• Added DiscordWebhook utility class for sending notifications
• Integrated webhook notifications into logger for key events:
  • Bot started/stopped
  • Battle wins/losses
  • Error notifications
• Added Discord webhook URL field to UI (Misc tab)
• Updated dependencies to include requests package
• Added comprehensive documentation in README.md

Features

• Real-time Discord notifications for bot events
• Optional feature (can be disabled by leaving field empty)
• Non-blocking async notifications
• Graceful error handling (bot continues if webhook fails)
• Privacy-focused (webhook URLs stored locally only)

Testing

• [x] Tested Discord webhook notifications work correctly
• [x] Verified bot continues operating if webhook fails
• [x] Confirmed webhook URL is saved and persists between sessions
• [x] Tested all notification types (start, stop, wins, losses, errors)

Documentation

• [x] Updated README.md with setup instructions
• [x] Added examples and usage notes
• [x] Code includes comprehensive docstrings

[martinmiglio]

I liked this when it was 400 lines. It crept out of scope and is now squeezing in features unrelated to discord webhooks. I would prefer if it were broken up, one PR per feature.

[tsIsFried]

Yes it was a full mistake I pushed to the same branch on accident I'm not at my computer rn so I can't change anything tonight but will within a day

[tsIsFried]

I was planning on making a new pull for deck to send the deck stuff to a website and have that in the background for more deck images