Quality of life improvements

A batch of smaller improvements to organizing reports, attaching files, and finding your way around.

• Disabled record types are now visible in Settings, so you can see everything available to turn on rather than only what's already enabled.
• Drag and drop reports into folders on the All reports page, and folders now sort alphabetically.
• Paste files directly into the chat — screenshots and documents no longer need to go through the upload dialog.
• Press Cmd+Enter (or Ctrl+Enter) to send a message to Agnes. Plain Enter still starts a new line.
• Documentation is linked from the bottom of the sidebar.
• Clearer error messages throughout, including when a folder can't be edited and when a report fails to generate.