fix(ci): correct USER_UID env var in pre-commit workflow

[SaitejaKommi]

Summary

This PR fixes a typo in the pre-commit workflow where USER_IID was exported instead of USER_UID.

The correction ensures UID-based behavior remains consistent for Docker build/test steps in CI.

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Related issue

• Fixes: CI pre-commit workflow uses USER_IID instead of USER_UID #379

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What changed

• Updated one line in pre-commit.yml:
  • Replaced USER_IID with USER_UID

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Why this is needed

• Build scripts and container ownership logic expect USER_UID
• Prevents UID mismatches in CI environments
• Improves consistency for Docker-based workflow steps

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Scope

• pre-commit.yml (single-line change)

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Testing Done

• Backend unit tests: passed
• Backend integration tests: passed
• Frontend build: passed
• Frontend tests: passed in dev and prod modes