feat: Add comprehensive documentation suite and reorganize project structure

- Created complete documentation in docs/ directory
- Added PROJECT_OVERVIEW.md with feature highlights and getting started guide
- Added ARCHITECTURE.md with system design and technical details
- Added SECURITY.md with comprehensive security implementation guide
- Added DEVELOPMENT.md with development workflows and best practices
- Added DEPLOYMENT.md with production deployment instructions
- Added API.md with complete REST API documentation
- Added CONTRIBUTING.md with contribution guidelines
- Added CHANGELOG.md with version history and migration notes
- Reorganized all documentation files into docs/ directory for better organization
- Updated README.md with proper documentation links and quick navigation
- Enhanced project structure with professional documentation standards

android-icon-72x72.svg

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg width="72" height="72" viewBox="0 0 72 72" xmlns="http://www.w3.org/2000/svg">
+  <!-- Cloud -->
+  <g transform="translate(36, 18)">
+    <!-- Cloud body -->
+    <ellipse cx="0" cy="0" rx="21" ry="10.5" fill="#4A90E2"/>
+    <circle cx="-13" cy="-2" r="7.5" fill="#4A90E2"/>
+    <circle cx="13" cy="-2" r="7.5" fill="#4A90E2"/>
+    <circle cx="-6.5" cy="-6.5" r="5" fill="#4A90E2"/>
+    <circle cx="6.5" cy="-6.5" r="5" fill="#4A90E2"/>
+    
+    <!-- Cloud smile -->
+    <path d="M -6.5 2 Q 0 7 6.5 2" stroke="#FFFFFF" stroke-width="2" fill="none" stroke-linecap="round"/>
+    
+    <!-- Cloud eyes -->
+    <circle cx="-4" cy="-0.5" r="2" fill="#FFFFFF"/>
+    <circle cx="4" cy="-0.5" r="2" fill="#FFFFFF"/>
+    <circle cx="-4" cy="-0.5" r="1" fill="#333"/>
+    <circle cx="4" cy="-0.5" r="1" fill="#333"/>
+  </g>
+  
+  <!-- PC Monitor -->
+  <g transform="translate(36, 49)">
+    <!-- Monitor screen -->
+    <rect x="-18" y="-9" width="36" height="13.5" rx="1" fill="#2C3E50" stroke="#4A90E2" stroke-width="1.5"/>
+    <rect x="-16" y="-7" width="32" height="9.5" rx="0.5" fill="#34495E"/>
+    
+    <!-- Screen content -->
+    <rect x="-14" y="-6" width="4.5" height="1.2" fill="#4A90E2"/>
+    <rect x="-14" y="-4" width="6.5" height="0.6" fill="#7FB3D3"/>
+    <rect x="-5.5" y="-6" width="3.5" height="3.5" fill="#5DADE2"/>
+    <rect x="-1.5" y="-6" width="4.5" height="1.2" fill="#4A90E2"/>
+    
+    <!-- Monitor stand -->
+    <rect x="-2" y="4.5" width="4" height="7" fill="#34495E"/>
+    <rect x="-9" y="11.5" width="18" height="2" rx="0.5" fill="#2C3E50"/>
+  </g>
+</svg>