### Added
- **bStats Metrics Integration:** Plugin analytics for tracking usage patterns.
- Plugin ID: 28421
- Custom charts: storage mode, shop mode, web UI status, holdings status, tracked items count
- Fully anonymized data collection via bStats platform

- **Custom Shop GUI Enhancements:**
- **Holdings Button:** View your virtual holdings directly from category pages (slot 45)
- **Sort Button:** Cycle through sorting options (Name, Price, Change) in category pages (slot 53)
- **Filter-Based Auto-Population:** Categories now use `filter` property to automatically populate items
- Items matching category filters are dynamically included without manual listing

- **Default Market GUI Improvements:**
- Removed Amount button from main market view for cleaner interface
- Sort button moved to slot 49 for better layout
- Sort order fixed: Price and Change now sort descending (highest first)

### Fixed
- **Hotbar Click Blocking:** Fixed issue where players couldn't interact with their hotbar while market GUI was open
- **Sort Order:** Price and Change sorting now correctly shows highest values first (descending order)
- **Holdings Button:** Holdings icon in Custom Shop GUI now properly opens the holdings panel
- **`/ex market` Command:** Now correctly opens DEFAULT or CUSTOM shop based on `shop.mode` config setting

### Technical
- bStats dependency added with proper Shadow relocation (`org.bstats` → `org.lokixcz.theendex.bstats`)
- `MarketGUI.openHoldings()` made public for cross-GUI access
- Improved click event handling with proper cancellation placement