fix(ci): grant write permissions for release-please

GITHUB_TOKEN needs contents:write and pull-requests:write to create
release branches and PRs. The previous read-all was too restrictive.

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

Author: omalleyandy

.github/workflows/release-please.yml

@@ -3,7 +3,9 @@ on:
     branches:
       - main
 
-permissions: read-all
+permissions:
+  contents: write
+  pull-requests: write
 name: release-please
 
 jobs: