feat(campaigns): delete campaign button + defer Jira to Activate

- Backend: add DELETE /campaigns/{id}?delete_tests=bool endpoint
- Backend: add delete_campaign() service — handles draft-only restriction,
  optional test deletion, nullifies child campaign FKs
- Backend: remove early Jira ticket creation from POST /campaigns,
  POST /campaigns/{id}/tests, and POST /campaigns/from-threat-actor
- Backend: activate endpoint now creates campaign Jira ticket if missing,
  then creates test tickets (all deferred from creation to activation)
- Frontend: add deleteCampaign() API function to campaigns.ts
- Frontend: two-step confirmation dialog on CampaignDetailPage —
  first confirms deletion, then asks whether to also delete associated tests

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

backend/app/services/campaign_crud_service.py

@@ -425,6 +425,62 @@ def schedule_campaign(
     return campaign
 
 
+def delete_campaign(
+    db: Session,
+    campaign_id: str,
+    *,
+    deleter_id: uuid.UUID,
+    deleter_role: str,
+    delete_tests: bool = False,
+) -> None:
+    """Delete a campaign.
+
+    Only draft campaigns can be deleted unless the caller is admin.
+    If delete_tests=True, the associated Test objects are also deleted.
+    Does not commit; caller commits.
+    """
+    campaign = db.query(Campaign).filter(Campaign.id == campaign_id).first()
+    if not campaign:
+        raise EntityNotFoundError("Campaign", campaign_id)
+
+    if campaign.status != "draft" and deleter_role != "admin":
+        raise BusinessRuleViolation("Only draft campaigns can be deleted")
+
+    if str(campaign.created_by) != str(deleter_id) and deleter_role != "admin":
+        raise PermissionViolation("Only the creator or admin can delete this campaign")
+
+    # Collect test IDs before removing associations
+    campaign_tests = (
+        db.query(CampaignTest).filter(CampaignTest.campaign_id == campaign_id).all()
+    )
+    test_ids = [ct.test_id for ct in campaign_tests]
+
+    # Remove CampaignTest join rows (clear depends_on refs first to avoid FK cycles)
+    for ct in campaign_tests:
+        ct.depends_on = None
+    db.flush()
+    for ct in campaign_tests:
+        db.delete(ct)
+    db.flush()
+
+    # Optionally delete the associated tests
+    if delete_tests:
+        for test_id in test_ids:
+            test = db.query(Test).filter(Test.id == test_id).first()
+            if test:
+                db.delete(test)
+        db.flush()
+
+    # Null-out parent_campaign_id on child campaigns to avoid FK violation
+    db.query(Campaign).filter(Campaign.parent_campaign_id == campaign.id).update(
+        {"parent_campaign_id": None}
+    )
+    db.flush()
+
+    db.delete(campaign)
+    db.flush()
+
+
 def get_campaign_history(db: Session, campaign_id: str) -> dict:
     """List all child campaigns (execution history) of a recurring campaign.