fix(ci): update pnpm version to 10.x and fix lockfile compatibility

- Update GitHub Actions to use pnpm 10 instead of 8
- Remove frozen-lockfile setting from .npmrc
- Regenerate pnpm-lock.yaml with lockfileVersion 9.0
- Remove pnpm-workspace.yaml (not needed for single project)

.github/workflows/main.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Setup pnpm
         uses: pnpm/action-setup@v2
         with:
-          version: 8
+          version: 10
 
       - name: Get pnpm store directory
         id: pnpm-cache