feat (x): Create dedicated error handling module for X scraping through SN42

[teslashibe]

User Story:
As a subnet validator,
I want standardized error handling and custom exceptions for X Masa Protocol operations,
So that I can reliably handle and respond to different types of failures in a consistent way.

Acceptance Criteria:

• Create new file protocol/x/errors.py
• Define custom exceptions for common failure scenarios:
  • Rate limiting errors
  • Authentication failures
  • Network connectivity issues
  • Data validation errors
  • API response parsing errors
• Include error codes and human-readable messages
• Provide error classification methods (e.g., is_retryable, is_fatal)
• Add documentation for each exception class
• Include example usage in docstrings
• Add unit tests for all error scenarios

Technical Notes:

• Should integrate with existing error handling in profile.py and search.py
• Consider adding error recovery suggestions in error messages
• Implement proper exception inheritance hierarchy