feat(storage): add option to disable checksums and improve robustness of full_object_checksum validation

[chandra-siri]

This PR introduces performance options and robustness improvements to the asynchronous append operations in AsyncAppendableObjectWriter.

Key Changes:

1. Disable Checksums for Performance:

   • Added the enable_checksum optional parameter (default: True) to AsyncAppendableObjectWriter.append().
   • When set to False, the writer skips calculation of chunk-level CRC32C checksums in _WriteResumptionStrategy, improving append throughput.
   • Updated unit tests to verify that chunk-level checksums are omitted when disabled.

2. Robustness of Finalization Checksum Validation:

   • Implemented type checking (isinstance(int)) and range checking ([0, 2**32-1]) for full_object_checksum in finalize().
   • Wrapped stream receiving and response processing inside a try...finally block. This guarantees that the underlying stream is closed and local writer state variables are reset on mismatch exceptions/errors, preventing stream leaks.
   • Simplified the finalization request building code into a clean if-elif-else format.
   • Added corresponding unit tests verifying validation error exceptions and proper stream cleanup.

[gemini-code-assist]

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[chandra-siri]

review / submit after #17658

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[chandra-siri]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces an enable_checksum parameter to control CRC32C checksum calculations during async object writes, adds validation for full_object_checksum in finalize(), and ensures proper stream cleanup. Key feedback includes removing undocumented parameters from the download_ranges docstring, wrapping both send() and recv() in the try...finally block for robust cleanup, and explicitly rejecting boolean values in the full_object_checksum type check along with adding a corresponding unit test.