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>

routes/mods.js

@@ -121,8 +121,52 @@ router.get('/', async (req, res) => {
   }
 });
 
-// Install mod to world
-router.post('/install/:worldName/:modName', async (req, res) => {
+// Enable mod for world (configuration-based)
+router.post('/enable/:worldName/:modName', async (req, res) => {
+  try {
+    const { worldName, modName } = req.params;
+    
+    if (!paths.isValidWorldName(worldName) || !paths.isValidModName(modName)) {
+      return res.status(400).json({ error: 'Invalid world or mod name' });
+    }
+    
+    const worldPath = paths.getWorldPath(worldName);
+    const worldConfigPath = paths.getWorldConfigPath(worldName);
+    const globalModPath = paths.getModPath(modName);
+    
+    try {
+      await fs.access(worldPath);
+    } catch {
+      return res.status(404).json({ error: 'World not found' });
+    }
+    
+    try {
+      await fs.access(globalModPath);
+    } catch {
+      return res.status(404).json({ error: 'Mod not found' });
+    }
+    
+    // Read current world configuration
+    const config = await ConfigParser.parseWorldConfig(worldConfigPath);
+    
+    // Enable the mod
+    if (!config.enabled_mods) {
+      config.enabled_mods = {};
+    }
+    config.enabled_mods[modName] = true;
+    
+    // Write updated configuration
+    await ConfigParser.writeWorldConfig(worldConfigPath, config);
+    
+    res.redirect(`/mods?world=${worldName}&enabled=${modName}`);
+  } catch (error) {
+    console.error('Error enabling mod for world:', error);
+    res.status(500).json({ error: 'Failed to enable mod for world' });
+  }
+});
+
+// Copy mod to world (physical installation)
+router.post('/copy/:worldName/:modName', async (req, res) => {
   try {
     const { worldName, modName } = req.params;
     
@@ -149,20 +193,49 @@ router.post('/install/:worldName/:modName', async (req, res) => {
     
     try {
       await fs.access(targetModPath);
-      return res.status(409).json({ error: 'Mod already installed in world' });
+      return res.status(409).json({ error: 'Mod already copied to world' });
     } catch {}
     
     await fs.mkdir(worldModsPath, { recursive: true });
     await fs.cp(globalModPath, targetModPath, { recursive: true });
     
-    res.redirect(`/mods?world=${worldName}&installed=${modName}`);
+    res.redirect(`/mods?world=${worldName}&copied=${modName}`);
   } catch (error) {
-    console.error('Error installing mod to world:', error);
-    res.status(500).json({ error: 'Failed to install mod to world' });
+    console.error('Error copying mod to world:', error);
+    res.status(500).json({ error: 'Failed to copy mod to world' });
   }
 });
 
-// Remove mod from world
+// Disable mod from world (configuration-based)
+router.post('/disable/:worldName/:modName', async (req, res) => {
+  try {
+    const { worldName, modName } = req.params;
+    
+    if (!paths.isValidWorldName(worldName) || !paths.isValidModName(modName)) {
+      return res.status(400).json({ error: 'Invalid world or mod name' });
+    }
+    
+    const worldConfigPath = paths.getWorldConfigPath(worldName);
+    
+    // Read current world configuration
+    const config = await ConfigParser.parseWorldConfig(worldConfigPath);
+    
+    // Disable the mod
+    if (config.enabled_mods && config.enabled_mods[modName]) {
+      config.enabled_mods[modName] = false;
+    }
+    
+    // Write updated configuration
+    await ConfigParser.writeWorldConfig(worldConfigPath, config);
+    
+    res.redirect(`/mods?world=${worldName}&disabled=${modName}`);
+  } catch (error) {
+    console.error('Error disabling mod for world:', error);
+    res.status(500).json({ error: 'Failed to disable mod for world' });
+  }
+});
+
+// Remove mod from world (delete physical copy)
 router.post('/remove/:worldName/:modName', async (req, res) => {
   try {
     const { worldName, modName } = req.params;