Document weblog gzip requirement and batch processing behavior

[jordanpadams]

🗒️ Summary

Adds documentation clarifying:

• All weblog files must be gzip-compressed (.gz) when using --weblogs
• Pre-flight validation fails the entire request if any non-gzipped file is present
• Workarounds: compress files or use --exclude to filter non-gzipped files
• How batch processing works and that individual file failures do not fail the batch
• Pre-flight validation happens before batching, so validation failures prevent all uploads

⚙️ Test Data and/or Report

See github actions run.

♻️ Related Issues

• Fixes Upload of gzip files does not happen if it is batched with non-gzip files #336

🤓 Reviewer Checklist

Reviewers: Please verify the following before approving this pull request.

Security & Quality

• SonarCloud: Confirmed no new High or Critical security findings.
• Secrets Detection: Verified that the Secrets Detection scan passed and no sensitive information (keys, tokens, PII) is exposed.
• Code Quality: Code follows organization style guidelines and best practices for the specific language (e.g., PEP 8, Google Java Style).

Testing & Validation

• Test Accuracy: Verified that test data is accurate, representative of real-world PDS4 scenarios, and sufficient for the logic being tested.
• Coverage: Automated tests cover new logic and edge cases.
• Local Verification: (If applicable) Successfully built and ran the changes in a local or staging environment.

Documentation

• Documentation: README, Wiki, or inline documentation (Sphinx, Javadoc, Docstrings) have been updated to reflect these changes.

Maintenance

• Issue Traceability: The PR is linked to a valid GitHub Issue or Jira Ticket.
• Backward Compatibility: Confirmed that these changes do not break existing downstream dependencies or API contracts (or that breaking changes are clearly documented).

[nutjob4life]

Looks great, thanks! Docs look superb.

And tox likes it too:

  py313: OK (23.18=setup[1.32]+cmd[21.87] seconds)
  docs: OK (1.18=setup[0.53]+cmd[0.65] seconds)
  lint: OK (2.63=setup[0.01]+cmd[2.62] seconds)
  congratulations :) (27.05 seconds)

[c-suh]

Updated documentation beautifully explains the gzip requirement (#330) and misattributed error (#336).