Add a separate Scryfall card metadata refresh

## Problem
Settings allows users to refresh 17Lands ratings but provides no separate way to refresh the Scryfall-backed card metadata cache. The card metadata timestamp can therefore remain old, and the independent data sources and refresh lifecycles are unclear.

## Proposed change
Add a separate action in Data Status for refreshing canonical card metadata from Scryfall without coupling it to the 17Lands ratings refresh.

Show progress and errors for the Scryfall download, explain what the action downloads, and update only the card metadata timestamp after a successful cacheable refresh.

## Acceptance Criteria
- [ ] Data Status provides a clearly labeled control for refreshing Scryfall card metadata.
- [ ] The action forces a cacheable Scryfall metadata refresh without refreshing 17Lands ratings.
- [ ] Download progress and completion or failure are visible in Settings.
- [ ] A successful refresh advances the card metadata timestamp.
- [ ] A failed refresh preserves the previous cache and timestamp and shows an actionable error.
- [ ] The UI clearly distinguishes the Scryfall metadata refresh from the 17Lands ratings refresh.

Start in Settings' Data Status and trace the existing 17Lands ratings refresh path, then identify the Scryfall-backed card metadata cache and its timestamp handling. Done means the separate control reports progress and errors, refreshes only Scryfall metadata, advances the timestamp on success, and preserves the prior cache and timestamp on failure.

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