feat: Implement comprehensive audit logging

supabase/functions/process-selective-approval/index.ts

@@ -602,6 +602,35 @@ serve(async (req) => {
       console.error('[APPROVAL] Failed to update submission status:', { error: updateError.message });
     }
 
+    // Log audit trail for submission action
+    try {
+      const approvedCount = approvalResults.filter(r => r.success).length;
+      const rejectedCount = approvalResults.filter(r => !r.success).length;
+      
+      await supabaseClient.rpc('log_admin_action', {
+        _admin_user_id: authenticatedUserId,
+        _target_user_id: submission.user_id,
+        _action: finalStatus === 'approved' 
+          ? 'submission_approved' 
+          : finalStatus === 'partially_approved'
+            ? 'submission_partially_approved'
+            : 'submission_rejected',
+        _details: {
+          submission_id: submissionId,
+          submission_type: submission.submission_type,
+          items_approved: approvedCount,
+          items_rejected: rejectedCount,
+          total_items: approvalResults.length,
+          final_status: finalStatus,
+          has_dependency_failure: hasDependencyFailure,
+          reviewer_notes: reviewerNotes
+        }
+      });
+    } catch (auditError) {
+      // Log but don't fail the operation
+      console.error('[AUDIT] Failed to log admin action:', auditError);
+    }
+
     const duration = endRequest(tracking);
 
     return new Response(