Refactor: limit the number of cached files checked for existence

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 66.66667% with 3 lines in your changes missing coverage. Please review.

Project coverage is 93.20%. Comparing base (073a975) to head (fe37f7c).

Files	Patch %	Lines
src/types/files/fileCache.ts	66.66%	3 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1153 +/- ## ======================================= Coverage 93.20% 93.20% ======================================= Files 102 102 Lines 6371 6373 +2 Branches 1508 1409 -99 ======================================= + Hits 5938 5940 +2 - Misses 410 432 +22 + Partials 23 1 -22 ```

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[github-actions[bot]]

:test_tube: Branch testing instructions

This pull request can be tested locally with the following command:

npm exec --yes -- "github:emmercm/igir#emmercm/limit-file-cache-checks" [commands..] [options]

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