More Tools (Polymer) 1.8.1 for 1.21.4

Add French translation by @Lumiflag
Update Traditional Chinese translation by @yichifauzi
Make version comparison between clients and server more lenient
- The user will now only receive a nag message if the major version number differs
- Algorithmical changes will now cause a major version bump
There is a known issue that sometimes mending may not work when picking up experience. This happens very randomly and i honestly have no explanation for it.
- If this happens to you, switch your tool to the offhand and back, which might fix it.