Fix instant codemod matching colocated test files (#99795)
## Summary
- prevent `cache-components-instant-false` from adding route config to
colocated test, spec, and story files
- keep compound page extensions eligible while filtering common
non-route suffixes
- cover POSIX and Windows paths in the regression tests
## Verification
- `pnpm --filter @next/codemod build`
- `pnpm --filter @next/codemod test --runInBand
cache-components-instant-false.test.js`
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