Optimize memory usage and performance in fuzzy search (help menu + sidebar)

[coderabbitai]

Problem Description

Memory leak and performance issues in fuzzy search functionality affecting help menu (PR #1011) and potentially sidebar search.

SEVERE: Memory Leak in Search Operations

Location: src/internal/handle_modal.go in fuzzySearch() function

Issue: New slice allocations on every keystroke without cleanup:

haystack := []string{}          // New allocation every keystroke
idxMap := []int{}              // New allocation every keystroke
results := []helpMenuModalData{} // New allocation every keystroke

Impact:

• Memory usage grows with each search operation
• Garbage collection pressure increases
• Performance degrades during extended search sessions

Current State

• Similar pattern likely exists in sidebar fuzzy search
• No debouncing implemented for rapid typing
• Existing optimization comments in codebase acknowledge this issue

Suggested Solutions

1. Memory Pool Implementation

Reuse slices to reduce GC pressure:

type searchPool struct {
    haystack []string
    idxMap   []int  
    results  []helpMenuModalData
}

func (p *searchPool) reset() {
    p.haystack = p.haystack[:0]
    p.idxMap = p.idxMap[:0] 
    p.results = p.results[:0]
}

2. Input Debouncing

Implement 250ms debouncing to reduce excessive filtering:

// Debounce search input to avoid excessive filtering
searchDebouncer := time.NewTimer(250 * time.Millisecond)

3. Capacity Pre-allocation

Pre-allocate slices with expected capacity to reduce reallocations.

4. Performance Monitoring

Add metrics to track:

• Search operation duration
• Memory allocation patterns
• GC frequency during search

Scope

This optimization should be applied to:

• Help menu fuzzy search (immediate)
• Sidebar search functionality (if similar pattern exists)
• Any other fuzzy search implementations in the codebase

Acceptance Criteria

• Memory allocations reduced by implementing slice reuse
• Input debouncing implemented (250ms)
• Performance testing shows improved search responsiveness
• Memory usage remains stable during extended search sessions
• Existing optimization TODOs in code are addressed

References

• PR: feat: Add search functionality to help menu (#1009) #1011
• Review comment: feat: Add search functionality to help menu (#1009) #1011 (comment)
• Requested by: @lazysegtree

[lazysegtree]

Also, we can make this part async.