[typescript+python] Implement Proper Error Handling for Storage Operations

[bigboateng]

Problem

Storage operations (GCS, S3, Local, Redis) currently handle errors silently by:

• Logging errors but continuing execution
• Returning default values (empty arrays, empty directories)
• Not properly categorizing error types
• Not preserving error context

This leads to:

• Users not being alerted about storage failures
• Programs continuing with potentially invalid state
• Difficult debugging as errors are masked
• Risk of data corruption or loss

Proposed Solution

1. Create a hierarchy of storage errors:

   StorageError (base)
   ├── StorageAuthenticationError
   ├── StorageAccessError
   ├── StorageNetworkError
   └── StorageConfigurationError

2. Update storage providers to:

   • Properly detect and categorize errors
   • Throw appropriate error types
   • Include helpful error messages
   • Preserve original error as cause
   • Never silently continue with invalid state

3. Update BrowserState to:

   • Handle all storage errors appropriately
   • Prevent continuing with invalid state
   • Provide clear error messages to users

Implementation Steps

1. Create StorageError hierarchy
2. Update all storage providers to use proper error types
3. Update BrowserState error handling
4. Update examples to demonstrate proper error handling
5. Add error handling documentation

Impact

• Improved reliability of storage operations
• Better user feedback for storage issues
• Easier debugging of storage problems
• Prevention of silent failures
• Protection against invalid state

Current Behavior

// GCS Example
[GCS] Error during download from GCS: Could not load the default credentials
[GCS] Falling back to new empty state directory at /var/folders/...
✅ Browser state mounted successfully at: ...

// S3 Example
[S3] Error during download from S3: Access Denied
[S3] Falling back to new empty state directory at /var/folders/...
✅ Browser state mounted successfully at: ...

Additional Context

This issue is critical for all storage operations as it affects the reliability and integrity of browser state management. Users need immediate feedback when storage operations fail rather than silently continuing with potentially invalid state.