Enable PR-triggered JAMA literature harvest runs

Author: wang177777

.github/workflows/jama_network_open_harvest.yml

@@ -7,6 +7,10 @@ on:
       - '.github/workflows/jama_network_open_harvest.yml'
       - 'scripts/fetch_jama_network_open.py'
       - 'jama_trigger.txt'
+  pull_request:
+    paths:
+      - 'scripts/fetch_jama_network_open.py'
+      - 'jama_trigger_pr.txt'
 
 permissions:
   contents: write
@@ -66,6 +70,7 @@ jobs:
           retention-days: 7
 
       - name: Publish run pointer and preview
+        if: github.event_name == 'push'
         shell: bash
         run: |
           git config user.name 'github-actions[bot]'