Implement 100% atomic transaction rollout

Update actions.ts and ApprovalTransactionToggle.tsx to default to the new atomic transaction RPC flow. The feature flag can now be used to disable the new flow for emergency rollback.

src/components/admin/ApprovalTransactionToggle.tsx

@@ -11,11 +11,12 @@ import { Alert, AlertDescription } from '@/components/ui/alert';
  * - NEW: Atomic PostgreSQL transaction (true ACID guarantees)
  */
 export function ApprovalTransactionToggle() {
-  const [useRpcApproval, setUseRpcApproval] = useState(false);
+  const [useRpcApproval, setUseRpcApproval] = useState(true);
 
   useEffect(() => {
-    // Read feature flag from localStorage
-    const enabled = localStorage.getItem('use_rpc_approval') === 'true';
+    // NEW flow is default (100% rollout)
+    // Only disabled if explicitly set to 'false'
+    const enabled = localStorage.getItem('use_rpc_approval') !== 'false';
     setUseRpcApproval(enabled);
   }, []);
 
@@ -35,7 +36,7 @@ export function ApprovalTransactionToggle() {
           Approval Transaction Mode
         </CardTitle>
         <CardDescription>
-          Control which approval flow is used for moderation
+          Atomic Transaction RPC is now the default. Toggle OFF only for emergency rollback.
         </CardDescription>
       </CardHeader>
       <CardContent className="space-y-4">
@@ -56,10 +57,10 @@ export function ApprovalTransactionToggle() {
         </div>
 
         {useRpcApproval ? (
-          <Alert>
-            <CheckCircle2 className="h-4 w-4" />
+          <Alert className="border-green-500 bg-green-50 dark:bg-green-950">
+            <CheckCircle2 className="h-4 w-4 text-green-600" />
             <AlertDescription>
-              <strong>Atomic Transaction Mode Enabled</strong>
+              <strong className="text-green-600">Production Mode (100% Rollout) ✓</strong>
               <ul className="mt-2 space-y-1 text-sm">
                 <li>✅ True ACID transactions</li>
                 <li>✅ Automatic rollback on errors</li>
@@ -69,17 +70,17 @@ export function ApprovalTransactionToggle() {
             </AlertDescription>
           </Alert>
         ) : (
-          <Alert>
-            <AlertCircle className="h-4 w-4" />
+          <Alert className="border-orange-500 bg-orange-50 dark:bg-orange-950">
+            <AlertCircle className="h-4 w-4 text-orange-600" />
             <AlertDescription>
-              <strong>Legacy Mode Active</strong>
+              <strong className="text-orange-600">Emergency Rollback Mode Active ⚠️</strong>
               <ul className="mt-2 space-y-1 text-sm">
-                <li>⚠️ Manual rollback logic (error-prone)</li>
+                <li>⚠️ Using legacy manual rollback logic</li>
                 <li>⚠️ Risk of orphaned entities if edge function crashes</li>
                 <li>⚠️ No true atomicity guarantee</li>
               </ul>
-              <p className="mt-2 font-medium">
-                Consider enabling Atomic Transaction Mode for improved reliability.
+              <p className="mt-2 font-medium text-orange-600">
+                This mode should only be used temporarily if issues are detected with the atomic transaction flow.
               </p>
             </AlertDescription>
           </Alert>

src/lib/moderation/actions.ts

@@ -178,9 +178,9 @@ export async function approvePhotoSubmission(
  * @returns Action result
  */
 /**
- * Feature flag to enable atomic transaction RPC approval flow.
- * Set to true to use the new process-selective-approval-v2 edge function
- * that wraps the entire approval in a single PostgreSQL transaction.
+ * Feature flag: Use new atomic transaction RPC for approvals (v2)
+ * 
+ * ✅ DEFAULT: NEW atomic transaction flow (100% ROLLOUT)
  * 
  * Benefits of v2:
  * - True atomic transactions (all-or-nothing)
@@ -188,11 +188,11 @@ export async function approvePhotoSubmission(
  * - Network-resilient (edge function crash = auto rollback)
  * - Eliminates orphaned entities
  * 
- * To enable: localStorage.setItem('use_rpc_approval', 'true')
- * To disable: localStorage.setItem('use_rpc_approval', 'false')
+ * To disable NEW flow (emergency rollback): localStorage.setItem('use_rpc_approval', 'false')
+ * To re-enable NEW flow: localStorage.removeItem('use_rpc_approval')
  */
 const USE_RPC_APPROVAL = typeof window !== 'undefined' && 
-  localStorage.getItem('use_rpc_approval') === 'true';
+  localStorage.getItem('use_rpc_approval') !== 'false';
 
 export async function approveSubmissionItems(
   supabase: SupabaseClient,