Add French de-inflection

[impucky]

Follow-up to Salwynn's work in #1626
Resolves #1572

I haven't tested the rules thoroughly but I fixed everything I could notice in the transforms.
Let me know if I've overlooked anything.

[github-actions]

Playwright test results

 2 failed
 3 passed

Details

 5 tests across 4 suites
 8 minutes, 32 seconds
 68a5979

Failed tests

chromium › integration.spec.js › anki add
chromium › visual.spec.js › visual

[jamesmaa]

I think it's fine to merge as is. We don't currently have many French users but if they run into any issues they can report them to us. Would it be easy to add TODO's to all the missing coverage of grammar or is that too much work? With a file size this large it might better organized that way

[impucky]

Yeah that shouldn't be too bad, I'll try to get that in later today.

[codspeed-hq]

CodSpeed Performance Report

Merging #1668 will degrade performances by 32.65%

_{Comparing impucky:fr-deinflection (d92a02b) with master (daccc9f)}

Summary

❌ 1 (👁 1) regressions
✅ 2 untouched benchmarks

Benchmarks breakdown

	Benchmark	master	impucky:fr-deinflection	Change
👁	Translator.prototype.findKanji - (n=3)	2.7 ms	3.9 ms	-32.65%