[gabisonia]

Description

Generated synchronous outbox tests ignore CollectionName, allowing classes that should share an xUnit collection to run concurrently. Emit the configured [Collection] attribute in all 13 sync templates, the async relative-DataSchema template, and the causation template.

Regenerate all configured projects: the 208 changed provider test files each gain one attribute. Add 12 regression cases covering Sync, Async, and Causation suites, singular and plural configurations, omitted collection names, distinct collections for multiple outboxes, and duplicate attributes.

Related Issues

Fixes #4239.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the Contributing Guide
• I have checked relevant generated-test guidance in .agent_instructions/generated_tests.md and ADR 0035
• I have added/updated XML documentation for any public API changes (not applicable: no public API changes)
• I have added/updated tests as appropriate
• My changes follow the existing code style and conventions

Additional Notes

Validation:

• Generator suite on .NET 10: 292 passed.
• MSSQL suite on .NET 10 against the local database: 331 passed, 4 skipped.
• SQLite suite on .NET 10: 156 passed.
• Generator tests and MSSQL tests compile for .NET 9 and .NET 10; existing warnings remain.
• Regeneration across all 17 configured projects is reproducible; all 374 generated outbox test classes have the collection name specified by their provider configuration.
• git diff --check passes.

Other providers' integration suites and .NET 9 test execution were not run locally.

[iancooper]

Thanks @gabisonia