Add tier feature design spec, annual billing, fuel type normalization, and admin subscription management

- Add comprehensive tier feature matrix spec defining Free/Basic/Plus/Pro capabilities across recommendations, predictions, history, logs, tools, and family sharing
- Add `stripe_price_id_annual` column to plans table and rename existing column to `stripe_price_id_monthly`
- Normalize legacy fuel type aliases (petrol→e10, diesel→b7_standard) in users table
- Implement BillingController with checkout, portal, success/cancel routes supporting monthly/annual cadence
- Add admin subscription assignment in Filament user edit page with admin-granted subscription support
- Add DowngradeUserOnSubscriptionDeleted listener to disable WhatsApp/SMS preferences on subscription cancellation
- Add MissedNotificationsOverview widget to Filament user detail page
- Add PollFuelPricesTest covering auto-refresh scenarios
- Add PriceReliability enum with reliability classification based on price age
- Add fuelTypes.js constants file exporting FUEL_TYPES from window global

app/Enums/PriceReliability.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace App\Enums;
+
+use Illuminate\Support\Carbon;
+
+enum PriceReliability: string
+{
+    case Reliable = 'reliable';
+    case Stale = 'stale';
+    case Outdated = 'outdated';
+
+    public static function fromUpdatedAt(?Carbon $updatedAt): self
+    {
+        if ($updatedAt === null) {
+            return self::Outdated;
+        }
+
+        $hours = $updatedAt->diffInHours(now());
+
+        return match (true) {
+            $hours <= 72 => self::Reliable,
+            $hours <= 168 => self::Stale,
+            default => self::Outdated,
+        };
+    }
+
+    public function weight(): int
+    {
+        return match ($this) {
+            self::Reliable => 0,
+            self::Stale => 1,
+            self::Outdated => 2,
+        };
+    }
+
+    public function label(): string
+    {
+        return match ($this) {
+            self::Reliable => 'Reliable',
+            self::Stale => 'Older price — verify before driving',
+            self::Outdated => 'Outdated — may be inaccurate',
+        };
+    }
+}

app/Filament/Resources/UserResource/Widgets/MissedNotificationsOverview.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace App\Filament\Resources\UserResource\Widgets;
+
+use App\Models\NotificationLog;
+use App\Models\User;
+use Filament\Widgets\StatsOverviewWidget;
+use Filament\Widgets\StatsOverviewWidget\Stat;
+
+class MissedNotificationsOverview extends StatsOverviewWidget
+{
+    public ?User $record = null;
+
+    protected function getStats(): array
+    {
+        if ($this->record === null) {
+            return [];
+        }
+
+        $userId = $this->record->id;
+
+        $missedTodayByChannel = fn (string $channel): int => NotificationLog::where('user_id', $userId)
+            ->where('channel', $channel)
+            ->where('sent', false)
+            ->whereDate('created_at', today())
+            ->count();
+
+        $missedThisMonth = NotificationLog::where('user_id', $userId)
+            ->where('sent', false)
+            ->whereMonth('created_at', now()->month)
+            ->whereYear('created_at', now()->year)
+            ->count();
+
+        return [
+            Stat::make('SMS missed today', $missedTodayByChannel('sms'))
+                ->color($missedTodayByChannel('sms') > 0 ? 'warning' : 'gray'),
+            Stat::make('WhatsApp missed today', $missedTodayByChannel('whatsapp'))
+                ->color($missedTodayByChannel('whatsapp') > 0 ? 'warning' : 'gray'),
+            Stat::make('Total missed this month', $missedThisMonth)
+                ->color($missedThisMonth > 0 ? 'warning' : 'gray'),
+        ];
+    }
+}

app/Http/Controllers/BillingController.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace App\Http\Controllers;
+
+use App\Enums\PlanTier;
+use Illuminate\Http\RedirectResponse;
+use Illuminate\Http\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+class BillingController extends Controller
+{
+    /**
+     * Redirect the user to a Stripe Checkout session for the requested plan + cadence.
+     */
+    public function checkout(Request $request, string $tier, string $cadence): Response|RedirectResponse
+    {
+        abort_unless(in_array($tier, [PlanTier::Basic->value, PlanTier::Plus->value, PlanTier::Pro->value], true), 404);
+        abort_unless(in_array($cadence, ['monthly', 'annual'], true), 404);
+
+        $priceId = config("services.stripe.prices.{$tier}.{$cadence}");
+
+        abort_if(empty($priceId), 404, "No Stripe price configured for {$tier} {$cadence}");
+
+        return $request->user()
+            ->newSubscription('default', $priceId)
+            ->allowPromotionCodes()
+            ->checkout([
+                'success_url' => route('billing.success').'?session_id={CHECKOUT_SESSION_ID}',
+                'cancel_url' => route('billing.cancel'),
+            ]);
+    }
+
+    /** Redirect the user to the Stripe-hosted Customer Billing Portal. */
+    public function portal(Request $request): Response|RedirectResponse
+    {
+        return $request->user()->redirectToBillingPortal(route('dashboard'));
+    }
+
+    public function success(): RedirectResponse
+    {
+        return redirect()->route('dashboard')->with('status', 'subscription_started');
+    }
+
+    public function cancel(): RedirectResponse
+    {
+        return redirect()->route('dashboard')->with('status', 'subscription_cancelled');
+    }
+}

app/Listeners/DowngradeUserOnSubscriptionDeleted.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace App\Listeners;
+
+use App\Models\User;
+use App\Models\UserNotificationPreference;
+use Illuminate\Support\Facades\Cache;
+use Laravel\Cashier\Events\WebhookReceived;
+
+class DowngradeUserOnSubscriptionDeleted
+{
+    public function handle(WebhookReceived $event): void
+    {
+        if (($event->payload['type'] ?? null) !== 'customer.subscription.deleted') {
+            return;
+        }
+
+        $stripeCustomerId = $event->payload['data']['object']['customer'] ?? null;
+
+        if (! $stripeCustomerId) {
+            return;
+        }
+
+        $user = User::where('stripe_id', $stripeCustomerId)->first();
+
+        if (! $user) {
+            return;
+        }
+
+        UserNotificationPreference::query()
+            ->where('user_id', $user->id)
+            ->whereIn('channel', ['whatsapp', 'sms'])
+            ->update(['enabled' => false]);
+
+        Cache::tags(['plans'])->forget("plan_for_user_{$user->id}");
+    }
+}