feat(tui): add Ctrl+R prompt history search

[puranikyashaswin]

Issue #5062 requested bash-style reverse-i-search.

What does this PR do?

Adds Ctrl+R history search to the prompt. A dialog opens where you can fuzzy search through prompt history. Ctrl+R cycles matches, Enter selects.

Changes:

• Added history_search keybind (ctrl+r)
• Moved session_rename to leader+R to avoid conflict
• Added search() method using fuzzysort
• Created DialogHistorySearch component

How did you verify your code works?

Ran bun dev, submitted prompts, tested Ctrl+R search, fuzzy filtering, and selection.

Closes #5062

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential Duplicate PRs Found:

1. PR feat(tui): add ctrl+r history search #5775 - feat(tui): add ctrl+r history search

   • Directly addresses the same feature with identical naming

2. PR feat(tui): add inline Ctrl+R reverse-i-search for prompt history #6276 - feat(tui): add inline Ctrl+R reverse-i-search for prompt history

   • Implements reverse-i-search (the bash-style feature mentioned in issue [FEATURE]: Ctrl+R to search and navigate prompt history instead of just arrow keys #5062)

3. PR feat: add prompt history modal with search #6061 - feat: add prompt history modal with search

   • Adds a prompt history modal with search functionality

4. PR feat(tui): add prefix-filtered prompt history navigation #9021 - feat(tui): add prefix-filtered prompt history navigation

   • Implements history navigation with filtering

Why they're related: These PRs all implement history search/navigation for the prompt, addressing similar or overlapping functionality. PRs #5775 and #6276 appear to be direct duplicates of the current PR #12307, as they implement the same Ctrl+R history search feature. Check their status (merged/closed/open) to determine if this PR is truly new work or a re-implementation.