Updated terms and privacy policy, stronger trash retention, and usability fixes

This update brings our legal documents in line with how the service actually works, and tightens how we honor data retention promises.

• Updated the terms of service and privacy policy — added a minimum age requirement (14+), corrected the AI data-processing notice to match actual behavior, and cleaned up the revision history (see the addendum in each document)
• Voice transcripts of items in the trash are now excluded from automatic cleanup during the 30-day restore window — restoring an item brings its transcript back too
• Fixed the AI panel's open/closed preference being silently overwritten when opening an item from a link or signing back in
• Resizing the category sidebar is smoother, and its width now stays consistent across multiple open tabs
• Added screen reader labels to the canvas previous/next arrows
• (Android) Fixed widgets not refreshing after signing back in, and navigation being blocked inside notification popups (ships with the next app update)
• Plus general stability improvements