feat(inbounds): restore copy-clients-between-inbounds modal

The menu item, backend endpoint (POST /panel/api/inbounds/:id/copyClients),
and i18n keys were already in place after the Vue3 migration, but the modal
itself was never ported — clicking the menu just toasted "coming soon".

Adds CopyClientsModal.vue: source inbound dropdown (multi-user inbounds
except the target), per-client checkbox selection via a-table row-selection,
optional Flow override when the target supports TLS flow, and result toasts
for added/skipped/errors.

frontend/src/pages/inbounds/CopyClientsModal.vue

@@ -0,0 +1,185 @@
+<script setup>
+import { computed, ref, watch } from 'vue';
+import { useI18n } from 'vue-i18n';
+import { message } from 'ant-design-vue';
+
+import { HttpUtil, SizeFormatter, IntlUtil } from '@/utils';
+import { TLS_FLOW_CONTROL } from '@/models/inbound.js';
+
+const { t } = useI18n();
+
+const props = defineProps({
+  open: { type: Boolean, default: false },
+  dbInbound: { type: Object, default: null },
+  dbInbounds: { type: Array, default: () => [] },
+});
+
+const emit = defineEmits(['update:open', 'saved']);
+
+const FLOW_OPTIONS = Object.values(TLS_FLOW_CONTROL);
+
+const sourceInboundId = ref(null);
+const selectedEmails = ref([]);
+const flow = ref('');
+const saving = ref(false);
+
+const sources = computed(() => {
+  if (!props.dbInbound) return [];
+  return props.dbInbounds
+    .filter(
+      (row) =>
+        row.id !== props.dbInbound.id &&
+        typeof row.isMultiUser === 'function' &&
+        row.isMultiUser(),
+    )
+    .map((row) => {
+      let count = 0;
+      try { count = (row.toInbound().clients || []).length; } catch (_e) { /* ignore */ }
+      return { id: row.id, label: `${row.remark || `#${row.id}`} (${row.protocol}, ${count})` };
+    });
+});
+
+const sourceInbound = computed(() => {
+  if (!sourceInboundId.value) return null;
+  return props.dbInbounds.find((r) => r.id === sourceInboundId.value) || null;
+});
+
+const sourceClients = computed(() => {
+  const sb = sourceInbound.value;
+  if (!sb) return [];
+  let list = [];
+  try { list = sb.toInbound().clients || []; } catch (_e) { /* ignore */ }
+  const stats = new Map((sb.clientStats || []).map((s) => [s.email, s]));
+  return list
+    .filter((c) => c.email)
+    .map((c) => {
+      const s = stats.get(c.email);
+      const used = s ? (s.up || 0) + (s.down || 0) : 0;
+      let expiryLabel = t('unlimited');
+      if (c.expiryTime > 0) expiryLabel = IntlUtil.formatDate(c.expiryTime);
+      else if (c.expiryTime < 0) expiryLabel = `${-c.expiryTime / 86400000}d`;
+      return { email: c.email, trafficLabel: SizeFormatter.sizeFormat(used), expiryLabel };
+    });
+});
+
+const showFlow = computed(() => {
+  if (!props.dbInbound) return false;
+  try {
+    const inb = props.dbInbound.toInbound();
+    return !!(inb && typeof inb.canEnableTlsFlow === 'function' && inb.canEnableTlsFlow());
+  } catch (_e) { return false; }
+});
+
+const columns = computed(() => [
+  { title: t('pages.inbounds.email'), dataIndex: 'email', width: 280 },
+  { title: t('pages.inbounds.traffic'), dataIndex: 'trafficLabel', width: 140 },
+  { title: t('pages.inbounds.expireDate'), dataIndex: 'expiryLabel', width: 160 },
+]);
+
+const rowSelection = computed(() => ({
+  selectedRowKeys: selectedEmails.value,
+  onChange: (keys) => { selectedEmails.value = keys; },
+}));
+
+const title = computed(() => {
+  if (!props.dbInbound) return t('pages.client.copyFromInbound');
+  const target = props.dbInbound.remark || `#${props.dbInbound.id}`;
+  return `${t('pages.client.copyToInbound')} ${target}`;
+});
+
+watch(() => props.open, (next) => {
+  if (!next) return;
+  sourceInboundId.value = null;
+  selectedEmails.value = [];
+  flow.value = '';
+  saving.value = false;
+});
+
+watch(sourceInboundId, () => {
+  selectedEmails.value = [];
+});
+
+function selectAll() {
+  selectedEmails.value = sourceClients.value.map((c) => c.email);
+}
+function clearAll() {
+  selectedEmails.value = [];
+}
+
+async function ok() {
+  if (!sourceInboundId.value) {
+    message.error(t('pages.client.copySelectSourceFirst'));
+    return;
+  }
+  if (!props.dbInbound) return;
+  saving.value = true;
+  try {
+    const payload = {
+      sourceInboundId: sourceInboundId.value,
+      clientEmails: selectedEmails.value,
+    };
+    if (showFlow.value && flow.value) payload.flow = flow.value;
+    const msg = await HttpUtil.post(
+      `/panel/api/inbounds/${props.dbInbound.id}/copyClients`,
+      payload,
+    );
+    if (!msg?.success) return;
+    const obj = msg.obj || {};
+    const addedCount = (obj.added || []).length;
+    const errorList = obj.errors || [];
+    if (addedCount > 0) {
+      message.success(`${t('pages.client.copyResultSuccess')}: ${addedCount}`);
+    } else {
+      message.warning(t('pages.client.copyResultNone'));
+    }
+    if (errorList.length > 0) {
+      message.error(`${t('pages.client.copyResultErrors')}: ${errorList.join('; ')}`);
+    }
+    emit('saved');
+    emit('update:open', false);
+  } finally {
+    saving.value = false;
+  }
+}
+
+function close() {
+  if (saving.value) return;
+  emit('update:open', false);
+}
+</script>
+
+<template>
+  <a-modal :open="open" :title="title" :ok-text="t('pages.client.copySelected')" :cancel-text="t('close')"
+    :confirm-loading="saving" :mask-closable="false" width="720px" @ok="ok" @cancel="close">
+    <a-space direction="vertical" :style="{ width: '100%' }">
+      <div>
+        <div :style="{ marginBottom: '6px' }">{{ t('pages.client.copySource') }}</div>
+        <a-select v-model:value="sourceInboundId" :style="{ width: '100%' }" allow-clear>
+          <a-select-option v-for="item in sources" :key="item.id" :value="item.id">
+            {{ item.label }}
+          </a-select-option>
+        </a-select>
+      </div>
+
+      <div v-if="sourceInboundId">
+        <a-space :style="{ marginBottom: '8px' }">
+          <a-button size="small" @click="selectAll">{{ t('pages.client.selectAll') }}</a-button>
+          <a-button size="small" @click="clearAll">{{ t('pages.client.clearAll') }}</a-button>
+        </a-space>
+        <a-table :columns="columns" :data-source="sourceClients" :pagination="false" size="small"
+          :row-key="(r) => r.email" :row-selection="rowSelection" :scroll="{ y: 280 }" />
+      </div>
+
+      <div v-if="showFlow">
+        <div :style="{ marginBottom: '6px' }">{{ t('pages.client.copyFlowLabel') }}</div>
+        <a-select v-model:value="flow" :style="{ width: '100%' }" allow-clear>
+          <a-select-option value="">{{ t('none') }}</a-select-option>
+          <a-select-option v-for="key in FLOW_OPTIONS" :key="key" :value="key">{{ key }}</a-select-option>
+        </a-select>
+        <div :style="{ marginTop: '4px', fontSize: '12px', opacity: 0.7 }">
+          {{ t('pages.client.copyFlowHint') }}
+        </div>
+      </div>
+    </a-space>
+  </a-modal>
+</template>

frontend/src/pages/inbounds/InboundsPage.vue

@@ -21,6 +21,7 @@ import InboundList from './InboundList.vue';
 import InboundFormModal from './InboundFormModal.vue';
 import ClientFormModal from './ClientFormModal.vue';
 import ClientBulkModal from './ClientBulkModal.vue';
+import CopyClientsModal from './CopyClientsModal.vue';
 import InboundInfoModal from './InboundInfoModal.vue';
 import QrCodeModal from './QrCodeModal.vue';
 import TextModal from '@/components/TextModal.vue';
@@ -88,6 +89,8 @@ const clientIndex = ref(null);
 
 const bulkOpen = ref(false);
 const bulkDbInbound = ref(null);
+const copyOpen = ref(false);
+const copyDbInbound = ref(null);
 
 // === Info / QR-code modals ===========================================
 const infoOpen = ref(false);
@@ -515,10 +518,8 @@ function onRowAction({ key, dbInbound }) {
       exportInboundClipboard(dbInbound);
       break;
     case 'copyClients':
-      // Copy-clients-from-inbound is a tiny dedicated modal in legacy
-      // (lets you tick clients to copy across inbounds). Defer to a
-      // future commit — surface a friendly message for now.
-      message.info('Copy clients across inbounds — coming soon');
+      copyDbInbound.value = dbInbound;
+      copyOpen.value = true;
       break;
     case 'delete':
       confirmDelete(dbInbound);
@@ -663,6 +664,8 @@ function onRowAction({ key, dbInbound }) {
         :ip-limit-enable="ipLimitEnable" :traffic-diff="trafficDiff" @saved="refresh" />
       <ClientBulkModal v-model:open="bulkOpen" :db-inbound="bulkDbInbound" :sub-enable="subSettings.enable"
         :tg-bot-enable="tgBotEnable" :ip-limit-enable="ipLimitEnable" @saved="refresh" />
+      <CopyClientsModal v-model:open="copyOpen" :db-inbound="copyDbInbound" :db-inbounds="dbInbounds"
+        @saved="refresh" />
       <InboundInfoModal v-model:open="infoOpen" :db-inbound="infoDbInbound" :client-index="infoClientIndex"
         :remark-model="remarkModel" :expire-diff="expireDiff" :traffic-diff="trafficDiff"
         :ip-limit-enable="ipLimitEnable" :tg-bot-enable="tgBotEnable" :sub-settings="subSettings"