v3.7.21

- New: Add setting to hide the AI Chat toolbar button (#16607)
- Improved: AI Chat: Persist conversation history and add a chat switcher (#16583) (#16498 by [@Rygaa](https://github.com/Rygaa))
- Improved: Improve how semantic search interacts with item IDs (#16652) (#16644 by [@personalizedrefrigerator](https://github.com/personalizedrefrigerator))
- Fixed: Fix AI configuration test failing on reasoning models (#16594)
- Fixed: Fix AppImage StartupWMClass (#16547) (#16434 by [@MiQ71](https://github.com/MiQ71))
- Fixed: Fix ENEX import failing on Evernote's unescaped ampersands (#16580)
- Fixed: Fix LMStudio compatibility (#16552) (#16539 by [@personalizedrefrigerator](https://github.com/personalizedrefrigerator))
- Fixed: Fix dropping notes into the whiteboard editor (#16565) (#16457 by [@personalizedrefrigerator](https://github.com/personalizedrefrigerator))
- Fixed: Fix notes and sub-folders are still marked as published after being moved out of a published folder (#16648) (#16647 by [@personalizedrefrigerator](https://github.com/personalizedrefrigerator))
- Fixed: Fix reasoning blocks leaking into AI chat replies (#16595)
- Fixed: Fix sync deadlock when Joplin Server rejects an item with HTTP 422 (#16544) (#16504)
- Fixed: Fix table editor losing and mis-rendering inline markdown (#16632)
- Fixed: Fix x-callback-url responses never reaching the calling app (#16497)