release_v0.5.0

This release includes the following changes:

New Features:
- Context Clear API: Added clear_async, get_clear_status, and synchronous clear
  methods with configurable timeout and state tracking
- SDK Telemetry: Session creation now records SDK version and release status
- Context Sync Enhancements: Introduced UploadMode and lifecycle enums for
  flexible synchronization policies
- Session Parameters: Made image_id optional in CreateSessionParams
- Browser Module: Added variables parameter to ActOptions for parameterized
  automation instructions
- Browser Module: Added use_vision parameter to ObserveOptions and ExtractOptions

API Changes:
- Added ClearContextRequest and ClearContextResponse models
- Enhanced ContextService with clear operations
- Updated ContextSync with new upload modes and lifecycle policies
- Added version_utils and _release modules for SDK versioning

Documentation:
- Updated API reference documentation for all modules
- Enhanced context usage guide and sync policy documentation
- Updated examples and guides to reflect new features
- Fixed documentation formatting issues

Testing:
- Added unit tests for Code, Command, FileSystem, ContextManager modules
- Added integration tests for context clear operations
- Added tests for recycle policy and file archive mode

Files Changed:
- 48 files modified, 1216 insertions(+), 511 deletions(-)
- New files: clear_context_request.py, clear_context_response.py,
  version_utils.py, _release.py, and multiple test files