## Summary
- Add `add_module()` and `compile_with_modules()` to the `Tester` test
framework
- Supports both separate `add_module()` calls and single-string
`#[filename]` syntax via `add_files()`
- Automatically scans module dependencies with `scan_precise`,
topologically sorts, builds PCMs in order, then compiles the main file
- Temporary PCM files cleaned up automatically in destructor
- Migrated `ModuleImport` and `ModuleReexport` semantic tokens tests to
use the new API
## Test plan
- [x] All 505 unit tests pass
- [x] All 113 integration tests pass
- [x] All 2 smoke tests pass
🤖 Generated with [Claude Code](https://claude.com/claude-code)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Tests**
* Centralized, module-aware test compilation with automatic module
discovery, dependency ordering, and cycle detection.
* Unified "compile with modules" flow; tests now add module sources
directly and no longer manage temporary module artifacts manually.
* Reduced duplicated compile/diagnostic logic and improved cleanup of
generated artifacts.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>