fix: Rebuild binary — TUI launches directly, no architecture leaks

Binary now runs `npx @openanalystinc/openanalyst-cli` to launch
the TUI seamlessly. No more headless mode fallback that hangs.
If Node.js missing, shows clean install message.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 10x-Anit