Add explicit permissions to workflow for security

Co-authored-by: jeremymanning <9030494+jeremymanning@users.noreply.github.com>

Author: Copilot

.github/workflows/auto_solver.yml

@@ -9,6 +9,9 @@ jobs:
   auto-solve:
     runs-on: ubuntu-latest
     if: github.repository_owner == 'ContextLab'  # only run if on the ContextLab (source) repository!
+    
+    permissions:
+      contents: write  # Required to push commits back to the repository
 
     steps:
       - name: Checkout repository