refactor: use TryFrom for Certificate and CertificateRecord conversions

[dlachaume]

Content

This PR includes the replacement of From implementations with fallible TryFrom for converting between Certificate and CertificateRecord.

This PR includes...

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• Branch
  • Tests are provided (if possible)
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  • CHANGELOG file is updated (if relevant)
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  • No new TODOs introduced

Issue(s)

Closes #2651

[Copilot]

Pull Request Overview

This PR refactors the conversion between Certificate and CertificateRecord types by replacing infallible From trait implementations with fallible TryFrom trait implementations. This change makes error handling explicit for conversions that could potentially fail during serialization/deserialization operations.

• Replaced From implementations with TryFrom for Certificate ↔ CertificateRecord conversions
• Updated all call sites to use try_into() with explicit error handling
• Modified repository methods and test helpers to handle conversion errors properly

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
mithril-aggregator/src/database/record/certificate.rs	Core implementation change from From to TryFrom for both conversion directions
mithril-aggregator/src/database/repository/certificate_repository.rs	Updated repository methods to handle fallible conversions with proper error propagation
mithril-aggregator/src/database/test_helper.rs	Modified test helper function to accept TryInto instead of Into
mithril-aggregator/src/tools/certificates_hash_migrator.rs	Updated test utility functions to use try_into().unwrap()
mithril-aggregator/src/database/query/certificate/insert_certificate.rs	Updated test code to use fallible conversions
mithril-aggregator/src/database/query/certificate/insert_or_replace_certificate.rs	Updated test code to use fallible conversions
mithril-aggregator/src/database/query/certificate/get_certificate.rs	Updated test code to use fallible conversions

[github-actions]

Test Results

    4 files  ±0    154 suites  ±0   22m 38s ⏱️ -10s
2 118 tests ±0  2 118 ✅ ±0  0 💤 ±0  0 ❌ ±0 
6 466 runs  ±0  6 466 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit dc4c8a5. ± Comparison against base commit 0122f3e.

♻️ This comment has been updated with latest results.

[Alenar]

LGTM 🐕

[turmelclem]

LGTM 🎸