refactor: Use generic type for usePrevious hook

[tassoevan]

Proposed changes

Small intervention on type safety by making usePrevious a generic (React hook) function.

Issue(s)

How to test or reproduce

Screenshots

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• Improvement (non-breaking change which improves a current function)
• New feature (non-breaking change which adds functionality)
• Documentation update (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works (if applicable)
• I have added necessary documentation (if applicable)
• Any dependent changes have been merged and published in downstream modules

Further comments

Summary by CodeRabbit

• Refactor
  • Internal code improvements for enhanced reliability and type safety.

[coderabbitai]

Walkthrough

The usePrevious hook was refactored to use TypeScript generics for improved type safety, renamed its parameter from value to state, changed the ref initialization from useRef(value) to useRef<T>(undefined), and removed the dependency array from the effect.

Changes

Cohort / File(s)	Summary
usePrevious Hook Refactoring app/lib/hooks/usePrevious.ts	Converted to generic function with typed ref initialization. Changed parameter name from value to state, updated return type to T | undefined, and removed dependency array from useEffect (now runs on every render instead of tracking [value]).
Dependencies package.json	Updated package dependencies with 4 additions and 4 removals.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Suggested labels

type: chore, community

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: converting the usePrevious hook to use generics for type safety, which aligns with the core refactoring work shown in the changeset.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@app/lib/hooks/usePrevious.ts`:
- Line 4: The ref initialization in the usePrevious hook causes a TypeScript
error because useRef<T>(undefined) doesn't allow undefined for concrete T;
change the ref to explicitly allow undefined by initializing as useRef<T |
undefined>(undefined) or by calling useRef<T | undefined>() so the ref type
becomes T | undefined (update the ref variable declaration named ref inside
usePrevious).

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ℹ️ Review info

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 566e100 and ade70fc.

📒 Files selected for processing (1)

• app/lib/hooks/usePrevious.ts

📜 Review details

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: ESLint and Test / run-eslint-and-test

🔇 Additional comments (1)

app/lib/hooks/usePrevious.ts (1)

3-11: Good type-safety improvement with behaviorally correct changes.

The generic refactor is a solid improvement. The implementation now properly handles the standard usePrevious pattern:

1. First render returns undefined — semantically correct, as there is no "previous" value on initial render.
2. Effect runs every render — ensures ref.current always holds the prior render's value, avoiding stale values when the tracked state doesn't change between renders.

The return type T | undefined accurately reflects this behavior. The only usage in the codebase (prevAction in ComposerInput.tsx) is fully compatible—it already handles the undefined case via its equality check.