fix(jira): create test tickets under campaign on activation

When a campaign is activated (Start), iterate all its tests and create
Jira tickets nested under the campaign ticket for any test that doesn't
already have one. Mirrors the pattern used in generate_campaign_from_actor.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/routers/campaigns.py

@@ -298,6 +298,29 @@ def activate_campaign(
         uow.commit()
     db.refresh(campaign)
 
+    # Create Jira test tickets for any campaign tests that don't have one yet,
+    # nested under the campaign's Jira ticket (non-fatal).
+    try:
+        from app.services.jira_service import (
+            auto_create_test_issue,
+            get_campaign_jira_key,
+            get_test_jira_key,
+        )
+        campaign_jira_key = get_campaign_jira_key(db, campaign_id)
+        if campaign_jira_key:
+            for ct in campaign.campaign_tests:
+                if ct.test and not get_test_jira_key(db, ct.test.id):
+                    auto_create_test_issue(
+                        db, ct.test, current_user,
+                        parent_ticket_override=campaign_jira_key,
+                    )
+            db.commit()
+    except Exception:
+        logger.exception(
+            "Jira test ticket creation failed during activation of campaign %s",
+            campaign_id,
+        )
+
     return serialize_campaign(db, campaign)