fix: exclude nested worktree directories from eslint

Same class of issue as the earlier vitest fix: linting from the main
checkout also picked up whatever worktree happened to still exist
under .claude/worktrees/, surfacing as a tsconfigRootDir conflict once
a second worktree was present on disk.

Claude-Session: https://claude.ai/code/session_01NhxA4npAXAxmCDEJt6kxSH

eslint.config.js

@@ -6,7 +6,10 @@ import tseslint from 'typescript-eslint'
 import { defineConfig, globalIgnores } from 'eslint/config'
 
 export default defineConfig([
-  globalIgnores(['dist']),
+  // Git worktrees for in-progress branches live nested under .claude/worktrees/
+  // in this project's dev setup — without this, linting from the main checkout
+  // also lints each worktree's full copy of the source tree.
+  globalIgnores(['dist', '.claude/worktrees/**']),
   {
     files: ['**/*.{ts,tsx}'],
     extends: [