ci(tracker-core): add DB compatibility matrix coverage for issue #1703

[josecelano]

Summary

• add saturation regression tests for large download counters in HTTP and UDP scrape responses
• add MySQL image-tag injection for tracker-core DB driver tests
• add a dedicated database-compatibility job between unit and e2e with a MySQL 8.0/8.4 matrix
• run compatibility tests via Rust test command with explicit env vars and feature-gated compatibility suite
• update issue spec docs/issues/1703-1525-01-persistence-test-coverage.md to match the implemented workflow

Closes #1703

[Copilot]

Pull request overview

This PR expands persistence/driver CI coverage by adding a dedicated database-compatibility job (MySQL matrix) and adds regression coverage for large scrape counters, while updating the related issue spec documentation.

Changes:

• Add UDP scrape counter saturation guard (u32 → i32::MAX) plus a regression unit test.
• Add MySQL image-tag injection for tracker-core MySQL driver tests and gate those tests behind a new db-compatibility-tests feature used by CI.
• Add a database-compatibility GitHub Actions job (MySQL 8.0 / 8.4 matrix) and update issue-spec docs to match the implemented workflow.

Reviewed changes

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

Show a summary per file

File	Description
packages/udp-tracker-server/src/handlers/scrape.rs	Saturating conversion helper for UDP i32 counters + regression test.
packages/tracker-core/src/databases/driver/mysql.rs	Feature-gate MySQL container tests and allow overriding MySQL image tag via env var.
packages/tracker-core/Cargo.toml	Add db-compatibility-tests feature flag for compatibility suite gating.
packages/http-protocol/src/v1/responses/scrape.rs	Add regression test ensuring very large downloaded values are encoded.
.github/workflows/testing.yaml	Add database-compatibility CI job with MySQL version matrix; e2e now depends on it.
docs/issues/1703-1525-01-persistence-test-coverage.md	Update spec to reflect workflow-based matrix approach.
docs/issues/1525-overhaul-persistence.md	Point the EPIC step to the updated spec filename.

Comments suppressed due to low confidence (1)

packages/tracker-core/src/databases/driver/mysql.rs:360

• The inline test instructions below still say the MySQL driver tests are executed with just TORRUST_TRACKER_CORE_RUN_MYSQL_DRIVER_TEST=true cargo test, but the module is now gated behind feature = "db-compatibility-tests". Update the instructions to include enabling that feature (so developers can still run these tests locally).

#[cfg(all(test, feature = "db-compatibility-tests"))]
mod tests {
    use std::sync::Arc;

    use testcontainers::core::IntoContainerPort;
    /*
    We run a MySQL container and run all the tests against the same container and database.

    Test for this driver are executed with:

    `TORRUST_TRACKER_CORE_RUN_MYSQL_DRIVER_TEST=true cargo test`

    The `Database` trait is very simple and we only have one driver that needs

---

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[codecov]

Codecov Report

❌ Patch coverage is 93.10345% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.44%. Comparing base (d51ef29) to head (f523745).
⚠️ Report is 5 commits behind head on develop.

Files with missing lines	Patch %	Lines
...ackages/tracker-core/src/databases/driver/mysql.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1705      +/-   ##
===========================================
+ Coverage    86.43%   86.44%   +0.01%     
===========================================
  Files          288      288              
  Lines        22672    22693      +21     
  Branches     22672    22693      +21     
===========================================
+ Hits         19596    19617      +21     
- Misses        2838     2842       +4     
+ Partials       238      234       -4     

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[josecelano]

ACK f523745