fix(payment): Stripe instance polluting alipay/wxpay limits groups

Root cause: Stripe instance had supported_types="card,alipay,link,wxpay"
but only card/link were mapped to "stripe" group. Stripe's alipay/wxpay
leaked into independent groups, and since Stripe had no limits configured,
it triggered the "any unlimited → all zeros" early return, making ALL
method limits show as zero.

Fix: pcGroupByPaymentType now routes ALL types from Stripe provider
instances to the "stripe" group (by checking ProviderKey, not sub-type).
Frontend: Stripe provider dialog shows single "Stripe" limits entry
instead of per-sub-type entries.

backend/internal/service/payment_config_limits.go

@@ -10,9 +10,6 @@ import (
 	"github.com/Wei-Shaw/sub2api/internal/payment"
 )
 
-// stripeSubTypes are types that should be aggregated under TypeStripe for user-facing display.
-var stripeSubTypes = map[string]bool{string(payment.TypeCard): true, string(payment.TypeLink): true}
-
 // GetAvailableMethodLimits collects all payment types from enabled provider
 // instances and returns limits for each, plus the global widest range.
 // Stripe sub-types (card, link) are aggregated under "stripe".
@@ -55,7 +52,8 @@ func (s *PaymentConfigService) GetMethodLimits(ctx context.Context, types []stri
 }
 
 // pcGroupByPaymentType groups instances by user-facing payment type.
-// Stripe sub-types (card, link) are merged under "stripe".
+// For Stripe providers, ALL sub-types (card, link, alipay, wxpay) map to "stripe"
+// because the user sees a single "Stripe" button, not individual sub-methods.
 // Uses a seen set to avoid counting one instance twice.
 func pcGroupByPaymentType(instances []*dbent.PaymentProviderInstance) map[string][]*dbent.PaymentProviderInstance {
 	typeInstances := make(map[string][]*dbent.PaymentProviderInstance)
@@ -70,15 +68,13 @@ func pcGroupByPaymentType(instances []*dbent.PaymentProviderInstance) map[string
 		}
 	}
 	for _, inst := range instances {
-		for _, t := range splitTypes(inst.SupportedTypes) {
-			if stripeSubTypes[t] || t == payment.TypeStripe {
-				add(payment.TypeStripe, inst)
-			} else {
-				add(t, inst)
-			}
-		}
+		// Stripe provider: all sub-types → single "stripe" group
 		if inst.ProviderKey == payment.TypeStripe {
 			add(payment.TypeStripe, inst)
+			continue
+		}
+		for _, t := range splitTypes(inst.SupportedTypes) {
+			add(t, inst)
 		}
 	}
 	return typeInstances
@@ -86,6 +82,7 @@ func pcGroupByPaymentType(instances []*dbent.PaymentProviderInstance) map[string
 
 // pcInstanceTypeLimits extracts per-type limits from a provider instance.
 // Returns (limits, true) if configured; (zero, false) if unlimited.
+// For Stripe instances, limits are stored under "stripe" key regardless of sub-types.
 func pcInstanceTypeLimits(inst *dbent.PaymentProviderInstance, pt string) (payment.ChannelLimits, bool) {
 	if inst.Limits == "" {
 		return payment.ChannelLimits{}, false

frontend/src/components/payment/PaymentProviderDialog.vue

@@ -22,7 +22,7 @@
           </label>
           <Select
             v-model="form.provider_key"
-            :options="(!!editing ? allKeyOptions : enabledKeyOptions) as any"
+            :options="(!!editing ? allKeyOptions : enabledKeyOptions) as SelectOption[]"
             :disabled="!!editing"
             @change="onKeyChange"
           />
@@ -219,6 +219,7 @@ import { reactive, computed, ref } from 'vue'
 import { useI18n } from 'vue-i18n'
 import BaseDialog from '@/components/common/BaseDialog.vue'
 import Select from '@/components/common/Select.vue'
+import type { SelectOption } from '@/components/common/Select.vue'
 import ToggleSwitch from './ToggleSwitch.vue'
 import type { ProviderInstance } from '@/types/payment'
 import type { TypeOption } from './providerConfig'
@@ -308,6 +309,10 @@ const resolvedFields = computed(() => {
 })
 
 const limitableTypes = computed(() => {
+  // Stripe: single "stripe" entry (one set of shared limits)
+  if (form.provider_key === 'stripe') {
+    return [{ value: 'stripe', label: 'Stripe' }]
+  }
   const selected = form.supported_types.filter(t => t !== 'easypay')
   return selected.map(v => {
     const found = props.allPaymentTypes.find(pt => pt.value === v)