Refactors card styling by moving color data to the `CardSet` model, removing the `Card.style` and `Pack.hex_color` fields.
- Adds `hex_color` to `CardSet` and a `CardSetColorMapping` model to populate it during import.
- Card importer now uses correct filename regexes to identify sets and apply color mappings.
- Card badge styling is now derived from the `CardSet`'s color, simplifying the data model.
Replaces the old clunky card multiselect with a dynamic Alpine.js component for an improved user experience.
- Introduces an API endpoint (`cards/api/search/`) for asynchronous searching.
- Provides a modern search-as-you-type interface with a `<noscript>` fallback.
