Enhanced Emacs debugging support for 2048 LLDB sessions

## Goal
Integrate Emacs with LLDB debugging workflow for 2048 analysis.

## Features to Implement
- [ ] Emacs LLDB integration using dap-mode or gud-lldb
- [ ] hexl-mode integration for viewing memory dumps
- [ ] Custom Elisp functions for common 2048 debug tasks
- [ ] Board state visualization in Emacs buffer
- [ ] Automatic state file parsing and display

## Proposed Workflow
1. Launch LLDB from Emacs with gud or dap-mode
2. Set breakpoints and control execution from Emacs
3. Dump memory states that auto-open in hexl-mode
4. Parse and visualize board state in dedicated buffer
5. Track score progression and state changes

## Files to Create
- `2048-debug-mode.el` - Main debugging mode
- `2048-hexl-integration.el` - hexl-mode enhancements
- `2048-board-viewer.el` - Board visualization

## Benefits
- Unified debugging environment
- Better hex editing with hexl-mode
- Scriptable debugging workflows
- Visual board representation alongside code