fix(kol): Phase 1 review — ACL lineage, expiry filters, tighter tenant scope

Addresses findings from consolidated Phase 1 code review:

- Add composite unique indexes + composite FKs so subscription_prompts and
  packages cannot reference mismatched (tenant_id, package_id, prompt_id)
  tuples, enforcing ACL lineage at the schema level.
- Add status CHECK constraints on all KOL tables as defense-in-depth.
- ListActiveSubscribersForPackage: drop meaningless tenant_id IS NOT NULL,
  add end_at expiry filter so fan-out skips expired subscribers.
- ApproveKolSubscription: add status='pending' guard to prevent double-approval.
- ListSubscriptionPromptsByTenant: join subscription/prompt/package/profile
  lifecycle so hidden/archived content no longer leaks; surface
  kol_display_name for UI.
- ListPublishedKolPackages: exclude expired subscribers from marketplace count.
- KolDashboardTrend: rewrite as CTE with day-series, returning both daily
  usage and new subscription counts.
- Remove cosmetic tenant_id IS NOT NULL from dashboard overview queries
  (the column is NOT NULL by schema).
- check_tenant_scope.sh: require tenant_id = sqlc.(n?)arg filter, reject
  tenant_id IS NOT NULL as a fake scope, maintain explicit exemption list.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/internal/tenant/repository/queries/kol_subscription.sql

@@ -23,11 +23,13 @@ WHERE tenant_id = sqlc.arg(tenant_id)::bigint
 ORDER BY created_at DESC;
 
 -- name: ListActiveSubscribersForPackage :many
+-- Cross-tenant read: used by platform admin for subscription fan-out.
+-- Excludes expired subscriptions so new prompts are not granted to them.
 SELECT id, tenant_id, package_id, status, approved_by, start_at, end_at, created_at, updated_at
 FROM kol_subscriptions
 WHERE package_id = sqlc.arg(package_id)
-  AND tenant_id IS NOT NULL
-  AND status = 'active';
+  AND status = 'active'
+  AND (end_at IS NULL OR end_at > NOW());
 
 -- name: ApproveKolSubscription :exec
 UPDATE kol_subscriptions
@@ -37,7 +39,8 @@ SET status = 'active',
     end_at = sqlc.arg(end_at),
     updated_at = NOW()
 WHERE id = sqlc.arg(id)
-  AND tenant_id = sqlc.arg(tenant_id)::bigint;
+  AND tenant_id = sqlc.arg(tenant_id)::bigint
+  AND status = 'pending';
 
 -- name: RevokeKolSubscription :exec
 UPDATE kol_subscriptions
@@ -55,10 +58,25 @@ ON CONFLICT (subscription_id, prompt_id) DO NOTHING;
 SELECT sp.id, sp.tenant_id, sp.subscription_id, sp.package_id, sp.prompt_id,
        sp.status, sp.granted_at, sp.revoked_at,
        p.name AS prompt_name, p.platform_hint, p.published_revision_no,
-       k.name AS package_name
+       k.name AS package_name,
+       pf.display_name AS kol_display_name
 FROM kol_subscription_prompts sp
-JOIN kol_prompts p ON p.id = sp.prompt_id AND p.deleted_at IS NULL
-JOIN kol_packages k ON k.id = sp.package_id AND k.deleted_at IS NULL
+JOIN kol_subscriptions s ON s.id = sp.subscription_id
+    AND s.tenant_id = sp.tenant_id
+    AND s.package_id = sp.package_id
+    AND s.status = 'active'
+    AND (s.end_at IS NULL OR s.end_at > NOW())
+JOIN kol_prompts p ON p.id = sp.prompt_id
+    AND p.package_id = sp.package_id
+    AND p.status = 'active'
+    AND p.published_revision_no IS NOT NULL
+    AND p.deleted_at IS NULL
+JOIN kol_packages k ON k.id = sp.package_id
+    AND k.status = 'published'
+    AND k.deleted_at IS NULL
+JOIN kol_profiles pf ON pf.id = k.kol_profile_id
+    AND pf.status = 'active'
+    AND pf.deleted_at IS NULL
 WHERE sp.tenant_id = sqlc.arg(tenant_id)::bigint
   AND sp.status = 'active'
 ORDER BY sp.granted_at DESC;