perf(campaign): batch tenant summaries

src/govoplan_campaign/backend/manifest.py

@@ -161,6 +161,26 @@ def _tenant_summary(session, tenant_id: str) -> dict[str, int]:
     return {"campaigns": session.query(Campaign).filter(Campaign.tenant_id == tenant_id).count()}
 
 
+def _tenant_summary_batch(session, tenant_ids) -> dict[str, dict[str, int]]:
+    from sqlalchemy import func
+
+    from govoplan_campaign.backend.db.models import Campaign
+
+    ids = tuple(dict.fromkeys(str(tenant_id) for tenant_id in tenant_ids if tenant_id))
+    if not ids:
+        return {}
+    rows = (
+        session.query(Campaign.tenant_id, func.count(Campaign.id))
+        .filter(Campaign.tenant_id.in_(ids))
+        .group_by(Campaign.tenant_id)
+        .all()
+    )
+    return {
+        tenant_id: {"campaigns": int(count)}
+        for tenant_id, count in rows
+    }
+
+
 def _campaigns_router(context: ModuleContext):
     from govoplan_campaign.backend.runtime import configure_runtime
 
@@ -236,6 +256,7 @@ manifest = ModuleManifest(
     route_factory=_campaigns_router,
     role_templates=ROLE_TEMPLATES,
     tenant_summary_providers=(_tenant_summary,),
+    tenant_summary_batch_providers=(_tenant_summary_batch,),
     nav_items=(
         NavItem(path="/campaigns", label="Campaigns", icon="campaign", required_any=CAMPAIGN_MODULE_REQUIRED_ANY, order=20),
     ),