Remove mago lint step from CI, keep formatting only

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: phanan

.github/workflows/lint.yml

@@ -27,6 +27,3 @@ jobs:
 
       - name: Check formatting
         run: mago fmt --check
-
-      - name: Lint
-        run: mago lint --reporting-format=github