Add checkout_objective RPC

Introduced a PostgreSQL function checkout_objective to atomically lock an objective. Replaced previous JS-based checkout with RPC call to set locked_by/locked_at when eligible, enabling safe first-time checkout and stale-lock recovery.

X-Lovable-Edit-ID: edt-04f69ba7-cbb8-4fd5-9a69-6fd0a72d9009
Co-authored-by: magnusfroste <38864257+magnusfroste@users.noreply.github.com>

Author: lovable-dev[bot]

src/integrations/supabase/types.ts

@@ -2850,6 +2850,10 @@ export type Database = {
       }
     }
     Functions: {
+      checkout_objective: {
+        Args: { p_locked_by?: string; p_objective_id: string }
+        Returns: boolean
+      }
       dispatch_automation_event: {
         Args: {
           entity_id?: string

supabase/functions/_shared/agent-reason.ts

@@ -417,17 +417,13 @@ export async function saveHeartbeatState(supabase: any, state: HeartbeatState):
 // ─── Atomic Task Checkout ─────────────────────────────────────────────────────
 
 export async function checkoutObjective(supabase: any, objectiveId: string): Promise<boolean> {
-  // Atomic: only succeeds if not locked or lock is stale (>30 min)
-  const staleThreshold = new Date(Date.now() - 30 * 60_000).toISOString();
-  const { data, error } = await supabase
-    .from('agent_objectives')
-    .update({ locked_by: 'heartbeat', locked_at: new Date().toISOString() })
-    .eq('id', objectiveId)
-    .or(`locked_by.is.null,locked_at.lt.${staleThreshold}`)
-    .select('id')
-    .maybeSingle();
+  // Atomic checkout via database function — prevents race conditions
+  const { data, error } = await supabase.rpc('checkout_objective', {
+    p_objective_id: objectiveId,
+    p_locked_by: 'heartbeat',
+  });
 
-  return !error && !!data;
+  return !error && data === true;
 }
 
 export async function releaseObjective(supabase: any, objectiveId: string): Promise<void> {

supabase/migrations/20260315230915_72a2c866-c2e0-4d46-87a9-e5bacc3394da.sql

@@ -0,0 +1,19 @@
+
+CREATE OR REPLACE FUNCTION public.checkout_objective(p_objective_id uuid, p_locked_by text DEFAULT 'heartbeat')
+RETURNS boolean
+LANGUAGE plpgsql
+SECURITY DEFINER
+SET search_path TO 'public'
+AS $$
+DECLARE
+  rows_affected integer;
+BEGIN
+  UPDATE agent_objectives
+  SET locked_by = p_locked_by, locked_at = now()
+  WHERE id = p_objective_id
+    AND (locked_by IS NULL OR locked_at < now() - interval '30 minutes');
+  
+  GET DIAGNOSTICS rows_affected = ROW_COUNT;
+  RETURN rows_affected > 0;
+END;
+$$;