feat: questionnaire management (Fasa 6)

- QuestionnaireSetController: full CRUD + publish/archive
- QuestionController: store, update, destroy, reorder
- ProgramQuestionnaireController: attach, confirm, detach
- Public/QuestionnaireController: show form, submit responses, double-submit guard
- Views: admin questionnaire CRUD, program questionnaire assign, public form + thankyou/already

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

resources/views/public/questionnaire/thankyou.blade.php

@@ -0,0 +1,41 @@
+@extends('layouts.public')
+
+@section('title', 'Terima Kasih — ' . $program->title)
+
+@section('hero')
+<h4 class="mb-1">{{ $program->title }}</h4>
+<div class="opacity-75 small">
+    <i class="bi bi-clipboard2-check me-1"></i>Maklum Balas Diterima
+</div>
+@endsection
+
+@section('content')
+
+<div class="checkin-card card p-4 text-center">
+    <div class="rounded-circle bg-success bg-opacity-10 d-inline-flex align-items-center justify-content-center mx-auto mb-3"
+         style="width:70px; height:70px;">
+        <i class="bi bi-heart-fill text-success" style="font-size:2rem;"></i>
+    </div>
+    <h5 class="fw-bold text-success mb-2">Terima Kasih!</h5>
+    <p class="text-muted small mb-4">
+        Maklum balas anda telah berjaya dihantar, <strong>{{ $participant->name }}</strong>.
+        Kami menghargai pandangan anda.
+    </p>
+
+    <div class="alert alert-info text-start small mb-4">
+        <i class="bi bi-award me-2"></i>
+        <strong>Sijil Digital (eCert)</strong> anda akan dihantar ke emel
+        @if($participant->email)
+        <strong>{{ $participant->email }}</strong>
+        @else
+        yang didaftarkan
+        @endif
+        setelah program tamat.
+    </div>
+
+    <a href="{{ route('public.semak.show', $qrCode->token) }}" class="btn btn-outline-primary btn-sm">
+        <i class="bi bi-search me-1"></i> Semak Status Sijil
+    </a>
+</div>
+
+@endsection