refactor: reorganize struct fields, add new handlers and storage backends

- [x] Reorder struct fields across codebase for consistency
- [x] Add analytics event handlers and tests
- [x] Add authentication API key management handlers and tests
- [x] Add pre-warming control handlers and tests
- [x] Implement S3 storage backend with tests
- [x] Implement SMB/CIFS storage backend with tests
- [x] Add CDN middleware tests
- [x] Integrate analytics tracking into cache manager
- [x] Add S3 and SMB storage initialization in app setup
- [x] Add CDN caching to proxy handlers
- [x] Remove distributed locking (Redis lock manager)
- [x] Remove proxy common package and utilities
- [x] Remove standalone HTTP server package
- [x] Remove logger middleware
- [x] Simplify error handling utilities
- [x] Update config with S3 and SMB options
- [x] Update cache manager signature to include analytics

pkg/storage/interface.go

@@ -52,21 +52,21 @@ type ListOptions struct {
 
 // StorageObject represents a stored object
 type StorageObject struct {
-	Key      string
-	Size     int64
 	Modified time.Time
+	Key      string
 	ETag     string
+	Size     int64
 }
 
 // StorageInfo contains detailed object information
 type StorageInfo struct {
-	Key         string
-	Size        int64
 	Modified    time.Time
-	ETag        string
-	ContentType string
 	Metadata    map[string]string
 	Checksums   *Checksums
+	Key         string
+	ETag        string
+	ContentType string
+	Size        int64
 }
 
 // Checksums contains file checksums