Add card browser with similar cards and performance optimizations

README.md

@@ -166,17 +166,13 @@ Explore the curated commander catalog.
 - MDFC merges and compatibility snapshots are handled automatically; use `--compat-snapshot` on the refresh script to emit an unmerged snapshot.
 
 ### Browse Cards
-Search and filter all 26,427 Magic cards.
-- **Filtering**: Search by name, themes (up to 5), color identity, type, rarity, CMC range, power/toughness
+Search and explore all 29,839 Magic cards.
+- **Search & Filters**: Smart autocomplete for card names and themes, multi-theme filtering (up to 5), color identity, type, rarity, CMC range, power/toughness
 - **Sorting**: Name A-Z/Z-A, CMC Low/High, Power High, EDHREC Popular
-- **Keyboard Shortcuts**: 
-  - `Enter`: Add first autocomplete match to theme filters
-  - `Shift+Enter`: Apply all active filters
-  - `Esc` (double-tap): Clear all filters
-  - `?` button (desktop): Show keyboard shortcuts reference
-- **Responsive Design**: Mobile-optimized with adaptive grid and touch controls
-- **Shareable URLs**: Filter state persists in URL for saving and sharing searches
-- Powered by `card_files/all_cards.parquet` with theme tag index for fast lookups
+- **Card Details** (optional): Enable with `ENABLE_CARD_DETAILS=1` for individual card pages with similar card recommendations
+- **Keyboard Shortcuts**: `Enter` to add matches, `Shift+Enter` to apply filters, double `Esc` to clear all
+- **Shareable URLs**: Filter state persists in URL for easy sharing
+- Fast lookups powered by pre-built card index and optional similarity cache (`SIMILARITY_CACHE_ENABLED=1`)
 
 ### Browse Themes
 Investigate theme synergies and diagnostics.