Adding Buffer Size and Custom Endpoint Flags to Az SFTP

[DevanshG1]

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Pull request overview

This pull request adds two new command-line flags to the az sftp connect command: --buffer-size for configuring SFTP transfer buffer size and --endpoint-suffix for specifying custom storage account endpoint suffixes. The changes enable users to optimize transfer performance and support custom Azure environments (e.g., Azure Government, China, or private clouds).

Changes:

• Added --buffer-size parameter to control SFTP transfer buffer size (default: 256 KB)
• Added --endpoint-suffix parameter to override cloud-specific endpoint detection
• Refactored _get_storage_endpoint_suffix to _resolve_endpoint_suffix with custom suffix support and validation

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/sftp/setup.py	Version bump from 1.0.0b1 to 1.0.0b2
src/sftp/HISTORY.rst	Release notes documenting the new parameters
src/sftp/azext_sftp/constants.py	Added DEFAULT_BUFFER_SIZE_BYTES constant (256 KB)
src/sftp/azext_sftp/_params.py	Added buffer_size and endpoint_suffix parameter definitions
src/sftp/azext_sftp/_help.py	Updated documentation and examples for new parameters
src/sftp/azext_sftp/sftp_info.py	Added buffer_size support to SFTPSession and build_args method
src/sftp/azext_sftp/custom.py	Renamed and enhanced endpoint resolution with validation; added buffer_size parameter
src/sftp/azext_sftp/tests/latest/test_sftp_info.py	Added unit tests for buffer_size default and custom values
src/sftp/azext_sftp/tests/latest/test_custom.py	Added tests for endpoint_suffix validation and cloud-specific resolution; updated mock references