Add test coverage for controlled FileInput component

[Copilot]

Addresses review feedback requesting automated tests for the controlled/uncontrolled behavior in FileInput.

Tests added

• Controlled mode: value prop controls displayed files, onChange called but display unchanged until parent updates value
• Uncontrolled mode: internal state manages files, display updates immediately on selection
• onChange callback: invoked with File[] | null on selection/clear/removal
• Mode detection: value={null} is controlled, value={undefined} is uncontrolled

Fixes in this PR

• Fixed TypeScript error: unused size parameter renamed to _size
• Fixed TypeScript error: added null check for array access removeButtons[0]
• Fixed TypeScript error: added optional chaining for onChange.mock.calls[0]?.[0]
• Ran Prettier to fix formatting issues

15 tests total, all passing.

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[Copilot]

Pull request overview

This PR adds comprehensive automated test coverage for the FileInput component's controlled and uncontrolled behavior patterns. The tests validate that the component correctly implements the controlled/uncontrolled paradigm where value={undefined} enables uncontrolled mode with internal state management, while value={null} or value={[...]} enables controlled mode where the parent component manages state.

• 15 new test cases covering controlled mode, uncontrolled mode, and onChange callbacks
• Tests verify that controlled components don't update internal state until parent updates value prop
• Validates proper mode detection based on whether the value prop is defined

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
packages/utah-design-system/src/components/FileInput.test.tsx	New test file with comprehensive coverage of controlled/uncontrolled behavior, file selection, clearing, and removal operations
package-lock.json	Automatic dependency resolution updates (peer dependency flag adjustments)

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[stdavis]

@copilot It looks like you have some linting errors. Please fix them. You can lint by running npm run lint.

[Copilot]

@copilot It looks like you have some linting errors. Please fix them. You can lint by running npm run lint.

Fixed in 11f9d68. The TypeScript errors were:

• Unused size parameter (renamed to _size)
• Missing null check on array index access
• Missing optional chaining on mock calls access

Also ran Prettier to fix formatting. All lint, type checks, and tests pass now.