Add refund action to booking list/detail with full-refund toggle

- New RefundBookingTableAction on the booking list row and detail page,
  refunding a Confirmed booking directly via RefundBookingAction — no need
  to hunt up its Payment on the Refunds resource first.
- Payment::refundableBalance() extracted from RefundBookingAction's private
  balance check so both refund forms can display and cap against it.
- RefundBookingAction::resolveRefundablePayment() made public for the same
  reason (round-trip leg resolution reused by the UI).
- Both refund forms (ProcessRefundAction and the new booking action) gain a
  "Full refund" toggle, on by default, which refunds the payment's whole
  remaining balance without requiring a manually typed amount. Turning it
  off reveals an amount field capped at the refundable balance.

app-modules/payment/src/Actions/RefundBookingAction.php

@@ -35,14 +35,7 @@ class RefundBookingAction
             throw RefundNotAllowedException::notConfirmed($booking);
         }
 
-        // Round trip: payment is combined on the outbound leg, so a return
-        // leg has no Payment of its own — refund against its linked leg's
-        // Payment instead (domain.md §2b). The Confirmed check above still
-        // applies to $booking itself, not the payment holder, so each leg
-        // remains independently cancellable/refundable.
-        $paymentBooking = $booking->is_return_leg ? ($booking->linkedBooking ?? $booking) : $booking;
-
-        $payment = $paymentBooking->payments()->where('status', PaymentStatus::Completed->value)->latest()->first();
+        $payment = $this->resolveRefundablePayment($booking);
 
         if ($payment === null) {
             throw RefundNotAllowedException::noCompletedPayment($booking);
@@ -80,10 +73,27 @@ class RefundBookingAction
         return $refund;
     }
 
+    /**
+     * The Completed Payment a refund against $booking would apply to.
+     * Public so the Filament refund forms can look up the same Payment to
+     * surface its refundable balance before staff submit an amount.
+     *
+     * Round trip: payment is combined on the outbound leg, so a return leg
+     * has no Payment of its own — resolve against its linked leg's Payment
+     * instead (domain.md §2b). The Confirmed check in handle() still applies
+     * to $booking itself, not the payment holder, so each leg remains
+     * independently cancellable/refundable.
+     */
+    public function resolveRefundablePayment(Booking $booking): ?Payment
+    {
+        $paymentBooking = $booking->is_return_leg ? ($booking->linkedBooking ?? $booking) : $booking;
+
+        return $paymentBooking->payments()->where('status', PaymentStatus::Completed->value)->latest()->first();
+    }
+
     private function assertWithinRefundableBalance(Payment $payment, string $amount): void
     {
-        $alreadyRefunded = (string) $payment->refunds()->where('status', RefundStatus::Completed->value)->sum('amount');
-        $remaining = bcsub((string) $payment->amount, $alreadyRefunded, 2);
+        $remaining = $payment->refundableBalance();
 
         if (bccomp($amount, $remaining, 2) === 1) {
             throw RefundNotAllowedException::exceedsRefundableBalance($payment, $amount, $remaining);

app-modules/payment/src/Filament/Actions/RefundBookingTableAction.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Modules\Payment\Filament\Actions;
+
+use Filament\Actions\Action;
+use Filament\Forms\Components\Textarea;
+use Filament\Forms\Components\TextInput;
+use Filament\Forms\Components\Toggle;
+use Filament\Notifications\Notification;
+use Filament\Schemas\Components\Utilities\Get;
+use Filament\Support\Icons\Heroicon;
+use Modules\Booking\Enums\BookingStatus;
+use Modules\Booking\Models\Booking;
+use Modules\Payment\Actions\RefundBookingAction;
+use Modules\Payment\Exceptions\RefundFailedException;
+use Modules\Payment\Exceptions\RefundNotAllowedException;
+
+/**
+ * Shared between BookingsTable (row action) and ViewBooking (header action)
+ * in the Booking module — lets staff refund a booking directly instead of
+ * hunting up its Payment on the Refunds resource (ProcessRefundAction). Both
+ * surfaces call the same RefundBookingAction used by the API.
+ */
+class RefundBookingTableAction
+{
+    public static function make(): Action
+    {
+        return Action::make('refund')
+            ->label('Refund')
+            ->icon(Heroicon::OutlinedReceiptRefund)
+            ->color('danger')
+            ->visible(fn (): bool => auth()->user()?->can('process_refunds') ?? false)
+            ->disabled(fn (Booking $record): bool => $record->status !== BookingStatus::Confirmed)
+            ->schema([
+                Toggle::make('full_refund')
+                    ->label('Full refund')
+                    ->live()
+                    ->default(true)
+                    ->helperText(fn (Booking $record): string => 'Refundable balance: '.(app(RefundBookingAction::class)
+                        ->resolveRefundablePayment($record)?->refundableBalance() ?? '0.00')),
+                TextInput::make('amount')
+                    ->numeric()
+                    ->minValue(0.01)
+                    ->visible(fn (Get $get): bool => ! $get('full_refund'))
+                    ->required(fn (Get $get): bool => ! $get('full_refund'))
+                    ->maxValue(fn (Booking $record): ?string => app(RefundBookingAction::class)
+                        ->resolveRefundablePayment($record)?->refundableBalance()),
+                Textarea::make('reason')
+                    ->required(),
+            ])
+            ->action(function (Booking $record, array $data): void {
+                $amount = $data['full_refund']
+                    ? app(RefundBookingAction::class)->resolveRefundablePayment($record)?->refundableBalance() ?? '0.00'
+                    : (string) $data['amount'];
+
+                try {
+                    app(RefundBookingAction::class)->handle(
+                        $record,
+                        $amount,
+                        $data['reason'],
+                        auth()->id(),
+                    );
+
+                    Notification::make()
+                        ->title('Refund processed')
+                        ->success()
+                        ->send();
+                } catch (RefundNotAllowedException|RefundFailedException $exception) {
+                    Notification::make()
+                        ->title('Refund failed')
+                        ->body($exception->getMessage())
+                        ->danger()
+                        ->send();
+                }
+            });
+    }
+}

app-modules/payment/src/Filament/Resources/Refunds/Actions/ProcessRefundAction.php

@@ -6,7 +6,9 @@ use Filament\Actions\Action;
 use Filament\Forms\Components\Select;
 use Filament\Forms\Components\Textarea;
 use Filament\Forms\Components\TextInput;
+use Filament\Forms\Components\Toggle;
 use Filament\Notifications\Notification;
+use Filament\Schemas\Components\Utilities\Get;
 use Filament\Support\Icons\Heroicon;
 use Modules\Payment\Actions\RefundBookingAction;
 use Modules\Payment\Enums\PaymentStatus;
@@ -43,11 +45,21 @@ class ProcessRefundAction
                             $payment->id => "{$payment->booking?->booking_ref} — {$payment->amount} {$payment->currency} (#{$payment->id})",
                         ]))
                     ->searchable()
+                    ->live()
                     ->required(),
+                Toggle::make('full_refund')
+                    ->label('Full refund')
+                    ->live()
+                    ->default(true)
+                    ->helperText(fn (Get $get): string => $get('payment_id')
+                        ? 'Refundable balance: '.(Payment::find($get('payment_id'))?->refundableBalance() ?? '0.00')
+                        : 'Select a payment to see its refundable balance.'),
                 TextInput::make('amount')
                     ->numeric()
                     ->minValue(0.01)
-                    ->required(),
+                    ->visible(fn (Get $get): bool => ! $get('full_refund'))
+                    ->required(fn (Get $get): bool => ! $get('full_refund'))
+                    ->maxValue(fn (Get $get): ?string => Payment::find($get('payment_id'))?->refundableBalance()),
                 Textarea::make('reason')
                     ->required(),
             ])
@@ -68,10 +80,12 @@ class ProcessRefundAction
                     return;
                 }
 
+                $amount = $data['full_refund'] ? $payment->refundableBalance() : (string) $data['amount'];
+
                 try {
                     app(RefundBookingAction::class)->handle(
                         $payment->booking,
-                        (string) $data['amount'],
+                        $amount,
                         $data['reason'],
                         auth()->id(),
                     );

app-modules/payment/src/Models/Payment.php

@@ -10,6 +10,7 @@ use Modules\Booking\Models\Booking;
 use Modules\Payment\Database\Factories\PaymentFactory;
 use Modules\Payment\Enums\PaymentMethod;
 use Modules\Payment\Enums\PaymentStatus;
+use Modules\Payment\Enums\RefundStatus;
 use Spatie\Activitylog\Models\Concerns\LogsActivity;
 use Spatie\Activitylog\Support\LogOptions;
 
@@ -74,4 +75,17 @@ class Payment extends Model
     {
         return $this->hasMany(Refund::class);
     }
+
+    /**
+     * What's left to refund on this Payment — its total minus whatever has
+     * already been completed-refunded (partial refunds supported, domain.md
+     * §6). Shared by RefundBookingAction's own guard and the Filament refund
+     * forms, which surface it to staff before they submit.
+     */
+    public function refundableBalance(): string
+    {
+        $alreadyRefunded = (string) $this->refunds()->where('status', RefundStatus::Completed->value)->sum('amount');
+
+        return bcsub((string) $this->amount, $alreadyRefunded, 2);
+    }
 }