feat(home): change claude-code default model to sonnet

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: stackptr

modules/home/development.nix

@@ -37,7 +37,7 @@ in {
           };
         };
         settings = {
-          model = "opus";
+          model = "sonnet";
           # Disabled in favor of Basic Memory MCP for cross-device access
           autoMemoryEnabled = false;
           permissions = {