feat(subscription): add Stripe server limit quantity adjustment flow

Introduce a new `UpdateSubscriptionQuantity` Stripe action to:
- preview prorated due-now and next-cycle recurring costs
- update subscription item quantity with proration invoicing
- revert quantity and void invoice when payment is not completed

Wire the flow into the Livewire subscription actions UI with a new adjust-limit modal,
price preview loading, and confirmation-based updates. Also refactor the subscription
management section layout and fix modal confirmation behavior for temporary 2FA bypass.

Add `Subscription::billingInterval()` helper and comprehensive Pest coverage for
quantity updates, preview calculations, failure/revert paths, and billing interval logic.

app/Actions/Stripe/UpdateSubscriptionQuantity.php

@@ -0,0 +1,192 @@
+<?php
+
+namespace App\Actions\Stripe;
+
+use App\Jobs\ServerLimitCheckJob;
+use App\Models\Team;
+use Stripe\StripeClient;
+
+class UpdateSubscriptionQuantity
+{
+    private StripeClient $stripe;
+
+    public function __construct(?StripeClient $stripe = null)
+    {
+        $this->stripe = $stripe ?? new StripeClient(config('subscription.stripe_api_key'));
+    }
+
+    /**
+     * Fetch a full price preview for a quantity change from Stripe.
+     * Returns both the prorated amount due now and the recurring cost for the next billing cycle.
+     *
+     * @return array{success: bool, error: string|null, preview: array{due_now: int, recurring_subtotal: int, recurring_tax: int, recurring_total: int, unit_price: int, tax_description: string|null, quantity: int, currency: string}|null}
+     */
+    public function fetchPricePreview(Team $team, int $quantity): array
+    {
+        $subscription = $team->subscription;
+
+        if (! $subscription?->stripe_subscription_id || ! $subscription->stripe_invoice_paid) {
+            return ['success' => false, 'error' => 'No active subscription found.', 'preview' => null];
+        }
+
+        try {
+            $stripeSubscription = $this->stripe->subscriptions->retrieve($subscription->stripe_subscription_id);
+            $item = $stripeSubscription->items->data[0] ?? null;
+
+            if (! $item) {
+                return ['success' => false, 'error' => 'Could not retrieve subscription details.', 'preview' => null];
+            }
+
+            $currency = strtoupper($item->price->currency ?? 'usd');
+
+            // Upcoming invoice gives us the prorated amount due now
+            $upcomingInvoice = $this->stripe->invoices->upcoming([
+                'customer' => $subscription->stripe_customer_id,
+                'subscription' => $subscription->stripe_subscription_id,
+                'subscription_items' => [
+                    ['id' => $item->id, 'quantity' => $quantity],
+                ],
+                'subscription_proration_behavior' => 'create_prorations',
+            ]);
+
+            // Extract tax percentage — try total_tax_amounts first, fall back to invoice tax/subtotal
+            $taxPercentage = 0.0;
+            $taxDescription = null;
+            if (! empty($upcomingInvoice->total_tax_amounts)) {
+                $taxAmount = $upcomingInvoice->total_tax_amounts[0] ?? null;
+                if ($taxAmount?->tax_rate) {
+                    $taxRate = $this->stripe->taxRates->retrieve($taxAmount->tax_rate);
+                    $taxPercentage = (float) ($taxRate->percentage ?? 0);
+                    $taxDescription = $taxRate->display_name.' ('.$taxRate->jurisdiction.') '.$taxRate->percentage.'%';
+                }
+            }
+            if ($taxPercentage === 0.0 && ($upcomingInvoice->tax ?? 0) > 0 && ($upcomingInvoice->subtotal ?? 0) > 0) {
+                $taxPercentage = round(($upcomingInvoice->tax / $upcomingInvoice->subtotal) * 100, 2);
+            }
+
+            // Recurring cost for next cycle — read from non-proration invoice lines
+            $recurringSubtotal = 0;
+            foreach ($upcomingInvoice->lines->data as $line) {
+                if (! $line->proration) {
+                    $recurringSubtotal += $line->amount;
+                }
+            }
+            $unitPrice = $quantity > 0 ? (int) round($recurringSubtotal / $quantity) : 0;
+
+            $recurringTax = $taxPercentage > 0
+                ? (int) round($recurringSubtotal * $taxPercentage / 100)
+                : 0;
+            $recurringTotal = $recurringSubtotal + $recurringTax;
+
+            // Due now = amount_due (accounts for customer balance/credits) minus recurring
+            $amountDue = $upcomingInvoice->amount_due ?? $upcomingInvoice->total ?? 0;
+            $dueNow = $amountDue - $recurringTotal;
+
+            return [
+                'success' => true,
+                'error' => null,
+                'preview' => [
+                    'due_now' => $dueNow,
+                    'recurring_subtotal' => $recurringSubtotal,
+                    'recurring_tax' => $recurringTax,
+                    'recurring_total' => $recurringTotal,
+                    'unit_price' => $unitPrice,
+                    'tax_description' => $taxDescription,
+                    'quantity' => $quantity,
+                    'currency' => $currency,
+                ],
+            ];
+        } catch (\Exception $e) {
+            \Log::warning("Stripe fetch price preview error for team {$team->id}: ".$e->getMessage());
+
+            return ['success' => false, 'error' => 'Could not load price preview.', 'preview' => null];
+        }
+    }
+
+    /**
+     * Update the subscription quantity (server limit) for a team.
+     *
+     * @return array{success: bool, error: string|null}
+     */
+    public function execute(Team $team, int $quantity): array
+    {
+        if ($quantity < 2) {
+            return ['success' => false, 'error' => 'Minimum server limit is 2.'];
+        }
+
+        $subscription = $team->subscription;
+
+        if (! $subscription?->stripe_subscription_id) {
+            return ['success' => false, 'error' => 'No active subscription found.'];
+        }
+
+        if (! $subscription->stripe_invoice_paid) {
+            return ['success' => false, 'error' => 'Subscription is not active.'];
+        }
+
+        try {
+            $stripeSubscription = $this->stripe->subscriptions->retrieve($subscription->stripe_subscription_id);
+            $item = $stripeSubscription->items->data[0] ?? null;
+
+            if (! $item?->id) {
+                return ['success' => false, 'error' => 'Could not find subscription item.'];
+            }
+
+            $previousQuantity = $item->quantity ?? $team->custom_server_limit;
+
+            $updatedSubscription = $this->stripe->subscriptions->update($subscription->stripe_subscription_id, [
+                'items' => [
+                    ['id' => $item->id, 'quantity' => $quantity],
+                ],
+                'proration_behavior' => 'always_invoice',
+                'expand' => ['latest_invoice'],
+            ]);
+
+            // Check if the proration invoice was paid
+            $latestInvoice = $updatedSubscription->latest_invoice;
+            if ($latestInvoice && $latestInvoice->status !== 'paid') {
+                \Log::warning("Subscription {$subscription->stripe_subscription_id} quantity updated but invoice not paid (status: {$latestInvoice->status}) for team {$team->name}. Reverting to {$previousQuantity}.");
+
+                // Revert subscription quantity on Stripe
+                $this->stripe->subscriptions->update($subscription->stripe_subscription_id, [
+                    'items' => [
+                        ['id' => $item->id, 'quantity' => $previousQuantity],
+                    ],
+                    'proration_behavior' => 'none',
+                ]);
+
+                // Void the unpaid invoice
+                if ($latestInvoice->id) {
+                    $this->stripe->invoices->voidInvoice($latestInvoice->id);
+                }
+
+                return ['success' => false, 'error' => 'Payment failed. Your server limit was not changed. Please check your payment method and try again.'];
+            }
+
+            $team->update([
+                'custom_server_limit' => $quantity,
+            ]);
+
+            ServerLimitCheckJob::dispatch($team);
+
+            \Log::info("Subscription {$subscription->stripe_subscription_id} quantity updated to {$quantity} for team {$team->name}");
+
+            return ['success' => true, 'error' => null];
+        } catch (\Stripe\Exception\InvalidRequestException $e) {
+            \Log::error("Stripe update quantity error for team {$team->id}: ".$e->getMessage());
+
+            return ['success' => false, 'error' => 'Stripe error: '.$e->getMessage()];
+        } catch (\Exception $e) {
+            \Log::error("Update subscription quantity error for team {$team->id}: ".$e->getMessage());
+
+            return ['success' => false, 'error' => 'An unexpected error occurred. Please contact support.'];
+        }
+    }
+
+    private function formatAmount(int $cents, string $currency): string
+    {
+        return strtoupper($currency) === 'USD'
+            ? '$'.number_format($cents / 100, 2)
+            : number_format($cents / 100, 2).' '.$currency;
+    }
+}