[Feature Request] Add defaultSessionColor field to settings.json for persistent session color configuration

Feature Request

Add a "defaultSessionColor" field to settings.json so users can set a persistent session color (e.g. "cyan") without needing to run /color every session

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.76
• Feedback ID: 017db3e4-c382-44b7-904a-12c39ad17bf1

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/sebabreguel/.local/share/claude/versions/2.1.76 (expected in multi-process scenarios)\n    at FvT (/$bunfs/root/src/entrypoints/cli.js:2417:2026)\n    at Lxq (/$bunfs/root/src/entrypoints/cli.js:2417:1170)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-14T02:57:38.742Z"}]