Add syncthing-dir-time-fixer to community tools

Tool Description

syncthing-dir-time-fixer - Automatically fixes directory modification times after Syncthing sync to show actual content modification times instead of sync times.

Repository: https://github.com/halapenyoharry/syncthing-dir-time-fixer

Features

• Monitors Syncthing Event API for sync completion
• Updates directory mtimes to match their newest file
• Cross-platform (Linux, macOS, Windows with WSL)
• Runs as system service (systemd/launchd)
• Memory-efficient with leak prevention
• Configurable delays and exclusions

Why It's Useful

While Syncthing deliberately doesn't sync directory timestamps (see syncthing/syncthing#3667), many users want to see when work was actually done, not when it was synced. This tool fills that gap without modifying Syncthing itself.

Event API Usage Example

This tool demonstrates proper Event API usage:

• Long polling for events
• Handling FolderCompletion events
• Memory management for long-running processes
• Proper session cleanup

Documentation

Could be added to:

• Community Contributions page
• Event API examples
• Third-party tools section

The tool respects Syncthing's design decisions while providing an optional enhancement for users who need it.

Start by reading the Community Contributions, Event API examples, and third-party tools sections of the documentation, then review the syncthing-dir-time-fixer repository linked in the issue. Done means the tool is added to the appropriate documentation section with its repository link, description, and relevant Event API details.