feat: show current model and effort level in terminal title bar

Feature Request

Current behavior:
The terminal/console title bar only shows process names, e.g. sourcekit-lsp • claude or caffeinate • claude.

Desired behavior:
Include the current model (Opus, Sonnet, Haiku) and effort level (auto, low, high) in the terminal title bar, e.g. sourcekit-lsp • claude (Opus, auto).

Why:
When running multiple Claude Code sessions or switching between models/effort levels, there's no quick visual indicator of which configuration is active. You have to check /model to confirm. Showing this in the title bar would make it immediately visible at a glance.