dir option is not respected with file addition detection

[sapphi-red]

Describe the bug

When there is a config like below, test/foo.test.ts will not run. (This is correct.)
But if you add test/bar.test.ts after running vitest, it gets included.

export default defineConfig({
  test: {
    dir: 'src',
    include: ['**/*.test.ts'],
  },
});

Maybe related to #981.

Reproduction

https://stackblitz.com/edit/vitest-dev-vitest-xrmrde?file=vite.config.ts&initialPath=__vitest__

1. Run npm run test.
2. See src/bar.test.ts is included and test/bar.test.ts is not included.
3. Add test/foo.test.ts.
4. Rerun will happen and test/foo.test.ts is included.

System Info

stackblitz

vitest 0.7.4

Used Package Manager

npm

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