Ad and purchases enabled (still need actual testing)

lib/screens/user_agreement_screen.dart

@@ -0,0 +1,128 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:provider/provider.dart';
+
+import '../services/app_state.dart';
+
+/// The very first thing shown on a fresh install — before the onboarding
+/// tour, before anything else — gating [MainShell] entirely until the user
+/// taps "I Agree" (see [AppRoot] in main.dart and
+/// [AppState.hasAcceptedUserAgreement]/[AppState.acceptUserAgreement]).
+/// Its whole purpose is the liability section below: this app stores data
+/// on the user's own device (and, optionally, their own cloud storage
+/// account) with no server or backend of ours involved, so we have no
+/// ability to recover anything for them if it's lost.
+class UserAgreementScreen extends StatelessWidget {
+  const UserAgreementScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = Theme.of(context).textTheme;
+
+    return Scaffold(
+      appBar: AppBar(title: const Text('User Agreement'), automaticallyImplyLeading: false),
+      body: SafeArea(
+        child: Column(
+          children: [
+            Expanded(
+              child: ListView(
+                padding: const EdgeInsets.all(20),
+                children: [
+                  Text(
+                    'Please read and accept the following before using Show Me The Fuel '
+                    'Refund.',
+                    style: textTheme.bodyLarge,
+                  ),
+                  const SizedBox(height: 20),
+                  _Section(
+                    title: 'Your Data Lives on Your Device',
+                    body:
+                        'Every vehicle, fuel receipt, and photo you log is stored locally on '
+                        'this device. If you connect a cloud storage account (Google Drive, '
+                        'Dropbox, OneDrive, or your own WebDAV server) in Settings, a copy is '
+                        'also kept there — in storage you control, not on any server we run. '
+                        "We don't operate a backend, and we don't have a copy of your data.",
+                  ),
+                  _Section(
+                    title: 'We Are Not Responsible for Your Data or Any Data Loss',
+                    body:
+                        'The developer is not responsible for your data, or for any loss, '
+                        'corruption, or unavailability of it, for any reason — including but '
+                        'not limited to device loss, theft, or damage; an uninstall or app/OS '
+                        'update; a bug in this app; or an outage or account issue with a cloud '
+                        'storage provider you connect. Backing up your data (by connecting a '
+                        'cloud storage account, and by keeping it connected and in good '
+                        'standing) is entirely your responsibility. If you never connect a '
+                        'backup, the only copy of your data is the one on this device.',
+                  ),
+                  _Section(
+                    title: 'Provided As-Is',
+                    body:
+                        'This app is provided "as is," without warranty of any kind, express or '
+                        'implied. Fuel and gallon values are read automatically from your '
+                        'receipt photos and may be misread — always review them before relying '
+                        'on them, including for a refund claim.',
+                  ),
+                  _Section(
+                    title: 'Not Tax or Legal Advice',
+                    body:
+                        "This app helps you organize receipts for Missouri's Motor Fuel Tax "
+                        'Refund program; it does not provide tax or legal advice, and does not '
+                        'guarantee your eligibility for any refund. The program itself is set '
+                        'by Missouri law, which can change at any time — always confirm current '
+                        'eligibility and rates with the Missouri Department of Revenue.',
+                  ),
+                  const SizedBox(height: 8),
+                ],
+              ),
+            ),
+            const Divider(height: 1),
+            Padding(
+              padding: const EdgeInsets.all(16),
+              child: Row(
+                children: [
+                  Expanded(
+                    child: OutlinedButton(
+                      onPressed: () => SystemNavigator.pop(),
+                      child: const Text('Decline'),
+                    ),
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: FilledButton(
+                      onPressed: () => context.read<AppState>().acceptUserAgreement(),
+                      child: const Text('I Agree'),
+                    ),
+                  ),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+class _Section extends StatelessWidget {
+  final String title;
+  final String body;
+
+  const _Section({required this.title, required this.body});
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = Theme.of(context).textTheme;
+    return Padding(
+      padding: const EdgeInsets.only(bottom: 20),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(title, style: textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w700)),
+          const SizedBox(height: 6),
+          Text(body, style: textTheme.bodyMedium),
+        ],
+      ),
+    );
+  }
+}