Refactor: Move _http_failure to module_status.py

[abhijeetnardele24-hash]

Closes #485

Changes

• Moved the duplicate _http_failure helper from cert_transparency.py and wayback.py into a single public annotate_http_failure function in module_status.py.
• Updated cert_transparency and wayback to use the new shared helper.
• Added a test in tests/test_module_status.py verifying status code 429, 503 (mapped to RATE_LIMITED) and 500 (mapped to ERROR).
• Ensured existing tests for these modules pass perfectly.

[github-actions]

Thanks for the first pull request here. CI needs a maintainer to approve the run before it starts, so it may sit for a bit before anything happens. pytest tests/ -q passing is the main thing I look at.

[Copilot]

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[NovaCode37]

Thanks. Two things got mixed together in this branch:

1. The subnet calculator commit here is the clean version I asked for in fix: translate subnet calculator labels (i18n) #467: hand-added keys, 12 lines per locale, no re-serialized JSON. Please force-push that branch (fix: translate subnet calculator labels) so fix: translate subnet calculator labels (i18n) #467 contains exactly this commit, and I'll merge fix: translate subnet calculator labels (i18n) #467.
2. Share one HTTP failure helper instead of copying it per module #485 is already taken by fix: share one HTTP failure helper (Closes #485) #486, which was opened about an hour and a half before this one, so I'm keeping it there. Please close this PR once fix: translate subnet calculator labels (i18n) #467 is updated.

[abhijeetnardele24-hash]

I have force-pushed the clean commit to #467 as requested! Closing this PR since #485 was already taken. Thank you!