ci: normalize SCL workbench and connect PR concurrency identity

Use PR-number scoped run groups consistent with routing policy acceptance; preserve main integration runs.

Author: masarray

.github/workflows/scl-assisted-connect-ci.yml

@@ -38,7 +38,7 @@ on:
       - '.github/workflows/scl-assisted-connect-ci.yml'
 
 concurrency:
-  group: scl-assisted-connect-${{ github.ref }}
+  group: scl-assisted-connect-${{ github.event.pull_request.number || github.ref }}
   cancel-in-progress: ${{ github.event_name == 'pull_request' }}
 
 jobs:

.github/workflows/scl-assisted-workbench-ci.yml

@@ -39,7 +39,7 @@ permissions:
   contents: read
 
 concurrency:
-  group: scl-assisted-workbench-${{ github.ref }}
+  group: scl-assisted-workbench-${{ github.event.pull_request.number || github.ref }}
   cancel-in-progress: ${{ github.event_name == 'pull_request' }}
 
 jobs: