🐛 Fix path error in koreader router

[aaronleopold]

This PR fixes the following error:

Wrong number of path arguments for `Path`. Expected 1 but got 2. Note that multiple parameters must be extracted with a tuple `Path<(_, _)>` or a struct `Path<YourParams>`

I just did the same fix I did when this happened for OPDS v1.2 after adding API key support to that router. The issue is that I can't force Axum to "ignore" the parent Path params for handlers of nested routers (e.g., :document). So when I construct a handler that only has one Path (e.g., Path(document): Path<String>) it rejects the request outright with that error.

Ideally, I don't need this work around but I haven't figured out how to achieve that wiht Axum yet

[codecov]

Codecov Report

Attention: Patch coverage is 14.28571% with 6 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
apps/server/src/routers/koreader/sync.rs	0.00%	6 Missing ⚠️

Files with missing lines	Coverage Δ
apps/server/src/errors.rs	26.00% <100.00%> (+0.49%)	⬆️
apps/server/src/routers/koreader/sync.rs	0.00% <0.00%> (ø)

[aaronleopold]

I was able to both push and pull progress from a book which has the koreader_hash set in the database. So I'm comfortable merging this 👍