Feat/handle mangadex

[EliasLd]

Summary

This PR adds full MangaDex support to goweeb and improves chapter/volume range handling across both the CLI and TUI.

MangaDex introduces a few constraints that existing providers did not have, such as language-based scan selection, provider-specific image request headers, and non-contiguous chapter availability. This branch adds the required provider implementation while also making range selection more generic and reusable for future providers.

Changes

MangaDex provider

• Add MangaDex catalog search using the public API.
• Use available translation languages as scan paths.
• Fetch and paginate chapter feeds by selected language.
• Deduplicate duplicate chapter uploads.
• Fetch page URLs through MangaDex@Home.
• Support MangaDex-specific image request headers.
• Add readable language labels for supported translation codes.
• Register MangaDex as a supported provider and document it in the provider table.

Flexible chapter and volume ranges

• Add support for non-contiguous available ranges.

• Display available chapter/volume ranges instead of only the total entry count.

• Add multi-range input support, including formats such as:

  • 10
  • 1-10
  • 10-
  • -10
  • 1-10,20-30
  • 1,5,10

• Automatically skip unavailable entries inside a requested range instead of treating gaps as errors.

• Share the same range parsing and filtering logic between the CLI and TUI.

• Improve CLI help output for the new range syntax.

• Update the TUI to validate selections against the actual discovered entries before starting a download.

Notes

MangaDex chapters that are only linked to external services such as MangaPlus are currently ignored. This provider only downloads chapters whose pages are hosted through MangaDex/MangaDex@Home.

Decimal chapter numbers such as 3.5 are also not handled yet and are currently skipped.

Both limitations can be addressed separately in future updates.