* Add shared sync statistics collection and provider sync summary UI
- Introduced `SyncStats::Collector` concern to centralize sync statistics logic, including account, transaction, holdings, and health stats collection.
- Added collapsible `ProviderSyncSummary` component for displaying sync summaries across providers.
- Updated syncers (e.g., `LunchflowItem::Syncer`) to use the shared collector methods for consistent stats calculation.
- Added rake tasks under `dev:sync_stats` for testing and development purposes, including fake stats generation with optional issues.
- Enhanced provider-specific views to include sync summaries using the new shared component.
* Refactor `ProviderSyncSummary` to improve maintainability
- Extracted `severity_color_class` to simplify severity-to-CSS mapping.
- Replaced `holdings_label` with `holdings_label_key` for streamlined localization.
- Updated locale file to separate `found` and `processed` translations for clarity.
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Signed-off-by: Juan José Mata <juanjo.mata@gmail.com>
Co-authored-by: Josh Waldrep <joshua.waldrep5+github@gmail.com>
Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>
