Implement configuration-based mod management and fix navigation spacing

## Major Features Added

### Configuration-Based Mod Management
- Implement proper Luanti mod system using load_mod_* entries in world.mt
- Add mod enable/disable via configuration instead of file copying
- Support both global mods (config-enabled) and world mods (physically installed)
- Clear UI distinction with badges: "Global (Enabled)", "World Copy", "Missing"
- Automatic registry verification to sync database with filesystem state

### Game ID Alias System
- Fix minetest_game/minetest technical debt with proper alias mapping
- Map minetest_game → minetest for world.mt files (matches Luanti internal behavior)
- Reference: c9d4c33174/src/content/subgames.cpp (L21)

### Navigation Improvements
- Fix navigation menu spacing and text overflow issues
- Change "Configuration" to "Config" for better fit
- Implement responsive font sizing with clamp() for better scaling
- Even distribution of nav buttons across full width

### Package Registry Enhancements
- Add verifyAndCleanRegistry() to automatically remove stale package entries
- Periodic verification (every 5 minutes) to keep registry in sync with filesystem
- Fix "already installed" errors for manually deleted packages
- Integration across dashboard, ContentDB, and installation workflows

## Technical Improvements

### Mod System Architecture
- Enhanced ConfigParser to handle load_mod_* entries in world.mt files
- Support for both configuration-based and file-based mod installations
- Proper mod type detection and management workflows
- Updated world details to show comprehensive mod information

### UI/UX Enhancements
- Responsive navigation with proper text scaling
- Improved mod management interface with clear action buttons
- Better visual hierarchy and status indicators
- Enhanced error handling and user feedback

### Code Quality
- Clean up gitignore to properly exclude runtime files
- Add package-lock.json for consistent dependency management
- Remove excess runtime database and log files
- Add .claude/ directory to gitignore

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

utils/paths.js

@@ -184,13 +184,33 @@ class LuantiPaths {
     // Map directory names to the actual game IDs that Luanti recognizes
     // For most cases, the directory name IS the game ID
     const gameIdMap = {
-      // Only add mappings here if you're certain they're needed
-      // 'minetest_game': 'minetest', // This mapping was incorrect
+      // Luanti internal alias mapping - see https://github.com/luanti-org/luanti/blob/c9d4c33174c87ede1f49c5fe5e8e49a784798eb6/src/content/subgames.cpp#L21
+      'minetest_game': 'minetest',
     };
     
     return gameIdMap[directoryName] || directoryName;
   }
 
+  mapGameIdForWorldCreation(gameId) {
+    // When creating worlds, map game IDs that Luanti expects to use different IDs internally
+    // This is the reverse of directory-based detection - we're setting what goes in world.mt
+    const worldGameIdMap = {
+      'minetest_game': 'minetest',  // Luanti expects 'minetest' in world.mt even for minetest_game
+    };
+    
+    return worldGameIdMap[gameId] || gameId;
+  }
+
+  mapInternalGameIdToDirectory(internalGameId) {
+    // Reverse mapping: convert internal game ID back to directory name for display/reference
+    // This helps when we read a world.mt with "minetest" but want to show "Minetest Game"
+    const reverseGameIdMap = {
+      'minetest': 'minetest_game',  // world.mt has 'minetest' but directory is 'minetest_game'
+    };
+    
+    return reverseGameIdMap[internalGameId] || internalGameId;
+  }
+
   async getInstalledGames() {
     const games = [];
     // For Flatpak and other sandboxed installations, only look in the configured data directory