🧹 [Code Health] Remove unused Iterable import in friction_parse.py and enforce ruff on CI/Pre-commit

[laurigates]

🎯 What: Removed unused typing.Iterable import from feedback-plugin/scripts/friction_parse.py. I also applied ruff format and ruff check --fix over the same file to keep standard code style. Additionally, I added ruff checks to both the pre-commit configuration and the GitHub actions CI pipeline to ensure better code health checking in the future.
💡 Why: Unused imports clutter the codebase and can occasionally lead to confusion. Fixing format standardizes the style. Running these checks on CI ensures that code quality doesn't drift.
✅ Verification: Verified ruff check passes after changes. Verified the feedback-plugin/ pytest suite completely passes (14 tests passed).
✨ Result: A cleaner friction_parse.py script without dead code logic and standardized format across the codebase enforced at commit time via .pre-commit-config.yaml and .github/workflows/plugin-pr-checks.yml.

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PR created automatically by Jules for task 10218288211361800122 started by @laurigates

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