fix: flakiness in e2e tests in the CI

[jpraynaud]

Content

This PR includes a fix for flakiness in the e2e tests in the CI which occurs when multiple clients are verifying Cardano database concurrently.

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• Branch
  • Tests are provided (if possible)
  • Crates versions are updated (if relevant)
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Issue(s)

Closes #2687

[Copilot]

Pull Request Overview

This PR addresses flakiness in end-to-end tests when multiple clients verify Cardano databases concurrently by introducing timestamp-based temporary directory providers to prevent file system conflicts.

• Adds a new TempDirectoryProvider trait and TimestampTempDirectoryProvider implementation for unique temporary directories
• Updates the CardanoDatabaseClient to use the new temporary directory provider instead of hardcoded paths
• Refactors digest file handling to use instance-specific temporary directories

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
mithril-client/src/utils/temp_dir_provider.rs	Introduces the TempDirectoryProvider trait and TimestampTempDirectoryProvider implementation
mithril-client/src/utils/mod.rs	Adds the new temp_dir_provider module to exports and reorganizes imports
mithril-client/src/client.rs	Integrates TimestampTempDirectoryProvider in the client constructor
mithril-client/src/cardano_database_client/proving.rs	Updates InternalArtifactProver to use the injected temp directory provider
mithril-client/src/cardano_database_client/api.rs	Updates CardanoDatabaseClient constructor and test infrastructure to accept temp directory provider
mithril-client/Cargo.toml	Bumps version from 0.12.30 to 0.12.31

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[github-actions]

Test Results

    4 files  ±0    164 suites  ±0   23m 49s ⏱️ + 1m 14s
2 180 tests ±0  2 180 ✅ ±0  0 💤 ±0  0 ❌ ±0 
6 702 runs  ±0  6 702 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit 42c8f9c. ± Comparison against base commit 6a7107e.

This pull request removes 1 and adds 1 tests. Note that renamed tests count towards both.

mithril-client ‑ cardano_database_client::proving::tests::download_and_verify_digests::download_and_verify_digest_should_return_digest_map_acording_to_beacon

mithril-client ‑ cardano_database_client::proving::tests::download_and_verify_digests::download_and_verify_digest_should_return_digest_map_according_to_beacon

♻️ This comment has been updated with latest results.

[turmelclem]

LGTM 👍