This fixes cycle panics in several ecosystem projects (moved to
`good.txt` in a following PR
https://github.com/astral-sh/ruff/pull/17834 because our mypy-primer job
doesn't handle it well if we move projects to `good.txt` in the same PR
that fixes `ty` to handle them), as well as in the minimal case in the
added mdtest. It also fixes a number of panicking fuzzer seeds. It
doesn't appear to cause any regression in any ecosystem project or any
fuzzer seed.
Re: #17526
## Summary
Add integration tests for Python Semantic Syntax for
`InvalidStarExpression`, `DuplicateMatchKey`, and
`DuplicateMatchClassAttribute`.
## Note
- Red knot integration tests for `DuplicateMatchKey` exist already in
line 89-101.
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## Test Plan
This is a test.
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