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>

views/layout.ejs

@@ -4,6 +4,9 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title><%= title %> | LuHost</title>
+    <% if (typeof csrfToken !== 'undefined' && csrfToken) { %>
+        <meta name="csrf-token" content="<%= csrfToken %>">
+    <% } %>
     <link rel="stylesheet" href="/static/css/style.css">
     <link rel="icon" type="image/x-icon" href="/static/favicon.ico">
 </head>
@@ -48,6 +51,11 @@
                     Worlds
                 </a>
             </div>
+            <div class="nav-item">
+                <a href="/mods" class="nav-link <%= currentPage === 'mods' ? 'active' : '' %>">
+                    Mods
+                </a>
+            </div>
             <div class="nav-item">
                 <a href="/extensions" class="nav-link <%= currentPage === 'extensions' ? 'active' : '' %>">
                     Extensions
@@ -60,7 +68,7 @@
             </div>
             <div class="nav-item">
                 <a href="/config" class="nav-link <%= currentPage === 'config' ? 'active' : '' %>">
-                    Configuration
+                    Config
                 </a>
             </div>
             <div class="nav-item">