fix: suppress StepFeedback on custom steps, fix resume stepState seeding, functional updater for step index

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/pages/ProceduralNavigationPage.tsx

@@ -221,8 +221,10 @@ export function ProceduralNavigationPage() {
       setRuntimeSteps(hydrated)
 
       const initialStates = new Map<string, StepState>()
-      for (const step of allSteps) {
-        initialStates.set(step.id, { notes: '', verificationValue: '', completedAt: null })
+      for (const step of hydrated) {
+        if (step.type === 'procedure_step') {
+          initialStates.set(step.id, { notes: '', verificationValue: '', completedAt: null })
+        }
       }
 
       // Hydrate completed steps from decisions
@@ -406,7 +408,7 @@ export function ProceduralNavigationPage() {
       toast.error('Failed to save custom step')
     }
 
-    setCurrentStepIndex(currentStepIndex + 1)
+    setCurrentStepIndex(prev => prev + 1)
   }
 
   const handleSaveForLater = async () => {
@@ -625,7 +627,7 @@ export function ProceduralNavigationPage() {
             </div>
           )}
 
-          {session && currentStep && (
+          {session && currentStep && !('isCustom' in currentStep && currentStep.isCustom) && (
             <div className="mt-3 flex justify-end">
               <StepFeedback stepId={currentStep.id} sessionId={session.id} />
             </div>