⚡ Bolt: [performance improvement] Optimize date sorting and memoization

[Dexploarer]

💡 What:
Optimized date-based string sorting in apps/app/src/components/ConversationsSidebar.tsx and apps/app/src/AppContext.tsx. Replaced instances of new Date(string).getTime() with Date.parse(string). In ConversationsSidebar.tsx, the sort calculation for sortedConversations was also wrapped in a useMemo hook. Added explanatory comments as requested.

🎯 Why:
Calling new Date(string).getTime() within .sort() callbacks inside hot rendering loops creates unnecessary Date object allocations, increasing Garbage Collection (GC) pressure. Using Date.parse() skips object allocation. Additionally, sorting the conversations array inside a functional component without useMemo forces an $O(N \log N)$ sort operation on every single render, which degrades UI responsiveness as the chat history grows.

📊 Impact:

• Prevents redundant array cloning and sorting on every render of the ConversationsSidebar.
• Significantly reduces GC pressure and object allocations in critical WebSocket event handlers (conversation-updated and proactive messages) in AppContext.

🔬 Measurement:

1. Build and start the app (cd apps/app && npm run dev).
2. Populate the UI with numerous conversations.
3. Observe smoother scrolling and less jitter in the sidebar when typing chat input or receiving new proactive WebSocket events, verifiable through Chrome DevTools Performance profiles (fewer Minor GC spikes).

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PR created automatically by Jules for task 5090205366837892724 started by @Dexploarer

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces key performance optimizations by refining how date strings are processed and how conversation lists are managed. The changes aim to reduce the overhead of object creation and redundant computations, leading to a more responsive user interface and decreased garbage collection activity within the application, particularly in areas with frequent data updates and sorting.

Highlights

• Optimized Date Sorting: Replaced new Date(string).getTime() with Date.parse(string) for date-based string sorting in AppContext.tsx and ConversationsSidebar.tsx. This change significantly reduces Date object allocations and garbage collection pressure during sorting operations.
• Memoized Conversation List: Wrapped the sortedConversations calculation in ConversationsSidebar.tsx with a useMemo hook. This prevents redundant $O(N \log N)$ sorting on every render, improving UI responsiveness, especially as the chat history grows.
• Improved Code Clarity: Added explanatory comments to the optimized code sections, detailing the purpose and benefits of using Date.parse() and useMemo.

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[gemini-code-assist]

Code Review

This pull request introduces targeted performance optimizations by replacing new Date().getTime() with the more efficient Date.parse() for date-string sorting and by memoizing a sorted array calculation with useMemo. These changes, applied in AppContext.tsx and ConversationsSidebar.tsx, are well-justified and correctly implemented. They effectively reduce garbage collection pressure and prevent unnecessary re-computations on re-renders, leading to a more responsive UI. The implementation is sound and I have no further recommendations.