🔧 ci: run the pipeline on develop as well as main

The PR now targets develop, which was branched from main. The workflow only
triggered on push and pull_request against main, so nothing would have run on
develop or on any future PR into it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SAcqrz3FcadkYr3xG32CjK

.github/workflows/ci.yml

@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [ main ]
+    branches: [ main, develop ]
   pull_request:
-    branches: [ main ]
+    branches: [ main, develop ]
 
 jobs:
   verify: