Metadata fixes and enhancements

[benoit74]

Rationale

Fix #76 Fix #77 Fix #78 Fix #79

Nota:

• I had to add a bunch of # pyright:ignore because the go() function is not returning types properly for the type checker. We already agreed this will be revisited at some point.
• code coverage is still pretty bad, but this is not easily fixable without lot of work, I did my best to already include some more tests

[codecov[bot]]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (72493a8) 24.90% compared to head (edaef40) 29.75%.

Files	Patch %	Lines
src/kolibri2zim/entrypoint.py	83.33%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #80 +/- ## ========================================== + Coverage 24.90% 29.75% +4.85% ========================================== Files 7 6 -1 Lines 775 773 -2 Branches 135 135 ========================================== + Hits 193 230 +37 + Misses 570 531 -39 Partials 12 12 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.