feat(apps): a sales expert can work inside their customer's account (D29)

Reported missing by the owner: in the reference an expert could open any
of their referred customers and use the app AS them — browse, see
balance and debt, place orders — «یکجورایی انگار با اکانت اون ها لاگین
کرده». D21 had deliberately left it out as a session-hijack primitive.
The owner asked for the capability back with the implementation left to
judgement, so the scope is the reference's and the mechanism is not.

Scope: everything, as the reference had it. Its axios interceptor
swapped the bearer token, so every request went as the customer,
document upload included. No route is closed in act-as mode.

Mechanism: the reference minted and handed over the customer's own
permanent api_token. Here the expert keeps their own token and sends
X-Act-As-Customer, resolved in one place — CustomerJwtStrategy
.validateExpert. That single point is why all 17 customer routes work
unchanged: validate() already returns a principal whose `id` is a
Customer id and every customer route reads it. It also fixes four real
defects of the original:

  - ownership is re-checked on EVERY request, with referredByAgentId in
    the same where clause as the id, so another expert's customer and a
    non-existent id both answer 403, and a customer moved to another
    expert loses access at once rather than at token expiry;
  - nothing durable is handed out — the reference's token sat in
    localStorage with no expiry and kept working after the expert left;
  - adminUserId survives, so an order placed this way is attributable;
    in the reference the request was literally the customer's;
  - 403 rather than 401, so the app clears the act-as state instead of
    logging a perfectly valid session out.

Performance: one findFirst on the primary key, only when the header is
present, and it replaces the trading-account lookup rather than adding
to it.

Three things the reference never needed, because it swapped the whole
session. queryCache's `me:` keys, favouritesStore and wageQuoteStore all
dropped their data on a TOKEN change, which act-as does not cause — so
an expert would have seen their own profile, orders, balance, ledger and
favourites inside the customer's account. The wage-quote one is the
money case: making charge is per customer, so the figure on screen would
not have been the one the order was priced at. And uploadDocument builds
its own headers, so an expert's upload would have been filed against
their own account, silently.

Added with no reference equivalent: a permanent «در حال مشاهده به‌عنوان
…» bar. There, impersonation was invisible once the token had been
swapped, and placing an order on the wrong customer's gold debt was one
tap away. It is also the exit — the reference's only way out was a
logout that ended the expert's own session too. The cart is cleared in
both directions.

CustomerJwtStrategy had no test coverage at all and is now where this
feature's whole authorisation boundary lives: act-as-customer.spec.ts
covers 11 cases, including the header being ignored on a customer token,
the no-header path asserting the extra query does not run, and a revoked
session short-circuiting before the header is read.

api: 308/308 tests, 28 suites; both apps vue-tsc clean.

اپ: کارشناس فروش می‌تواند وارد حساب مشتریان خود شود، وضعیتشان را ببیند و از طرفشان سفارش ثبت کند.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

apps/user-app-v2/src/views/expert/CustomerChoiceView.vue

@@ -14,15 +14,18 @@
     scope is commented out at ApiMobileController.php:187, so every referred
     customer appears whatever their state (D4: replicate, don't "fix")
 
-  Deliberately NOT ported — two things, both recorded in D21:
-  1. `changeUser` / act-as. The reference minted an api_token for each listed
-     customer (ApiMobileController.php:197-201) so the agent could act AS them.
-     That is a session-hijack primitive; every session here derives from the
-     caller's own token, so tapping a card opens their details instead.
-  2. The activate/deactivate toggle and the edit button, which posted to
-     `/customer/toggle-active` and the customer form. Those are admin-panel
-     operations here, and adding a write path to the app during a delivery is
-     not worth the risk. The state is shown, read-only.
+  `changeUser` / act-as IS ported — see `enterAccount` below and D29. It was
+  previously left out as a session-hijack primitive (D21); the owner asked for
+  it back, so the capability is the reference's but the mechanism is not. The
+  reference minted a permanent api_token per customer
+  (ApiMobileController.php:197-201) and swapped the bearer token; here the
+  expert keeps their own token and the client names the customer in a header,
+  which the server re-authorises on every request.
+
+  Still deliberately NOT ported (D21):
+  - The activate/deactivate toggle and the edit button, which posted to
+    `/customer/toggle-active` and the customer form. Those are admin-panel
+    operations here. The state is shown, read-only.
 
   Scope is the server's: `referredByAgentId` = this expert, from the token.
 -->
@@ -127,6 +130,9 @@
             <dd>{{ active.active === 1 ? 'فعال' : 'غیرفعال' }}</dd>
           </div>
         </dl>
+        <button type="button" class="cch__enter" :disabled="entering" @click="enterAccount(active)">
+          {{ entering ? 'در حال ورود…' : 'ورود به حساب این مشتری' }}
+        </button>
         <button type="button" class="cch__close" @click="detailOpen = false">بستن</button>
       </div>
     </Drawer>
@@ -135,6 +141,7 @@
 
 <script setup lang="ts">
 import { onMounted, ref } from 'vue'
+import { useRouter } from 'vue-router'
 import { Drawer } from 'ant-design-vue'
 import { Loading, PullRefresh } from 'vant'
 import Icon from '../../components/icon/Icon.vue'
@@ -142,6 +149,14 @@ import PageBar from '../../components/ui/PageBar.vue'
 import Spinner from '../../components/Spinner.vue'
 import SearchInput from '../../components/search/SearchInput.vue'
 import { api, type ExpertCustomer } from '../../api/client'
+import { useSessionStore } from '../../stores/session'
+import { useCartStore } from '../../stores/cartStore'
+import { toast } from '../../composables/useToast'
+
+const router = useRouter()
+const session = useSessionStore()
+const cart = useCartStore()
+const entering = ref(false)
 
 const rows = ref<ExpertCustomer[]>([])
 const loading = ref(false)
@@ -190,6 +205,30 @@ function openDetail(item: ExpertCustomer) {
   detailOpen.value = true
 }
 
+/**
+ * «ورود به حساب مشتری» — the reference's `changeUser`
+ * (customerChoice.vue:155-167). There it swapped the bearer token for the
+ * customer's own; here the session simply records who we are acting as and the
+ * API client names them in a header, which the server authorises per request.
+ *
+ * The cart is cleared in both directions: it lives in localStorage, so without
+ * this the expert's own basket would follow them into the customer's account
+ * and end up on the customer's order.
+ */
+async function enterAccount(item: ExpertCustomer) {
+  entering.value = true
+  try {
+    cart.clear()
+    session.setActingAs({ id: item.id, name: item.name ?? item.fullName ?? item.mobile ?? '' })
+    detailOpen.value = false
+    // Same destination as the reference, which returned to the dashboard.
+    await router.push({ name: 'userPage::hasSubRoute' })
+    toast.success(`وارد حساب ${item.name ?? ''} شدید`)
+  } finally {
+    entering.value = false
+  }
+}
+
 onMounted(load)
 </script>
 
@@ -347,7 +386,7 @@ onMounted(load)
   font-weight: 600;
 }
 
-.cch__close {
+.cch__enter {
   margin-top: 18px;
   width: 100%;
   padding: 13px;
@@ -359,5 +398,25 @@ onMounted(load)
   font-size: 14px;
   font-weight: 700;
   cursor: pointer;
+
+  &:disabled {
+    opacity: 0.6;
+    cursor: default;
+  }
+}
+
+/* Secondary now that "enter the account" is the primary action here. */
+.cch__close {
+  margin-top: 10px;
+  width: 100%;
+  padding: 13px;
+  border: 1px solid fade(@ink, 35%);
+  border-radius: 14px;
+  background: transparent;
+  color: @ink;
+  font-family: inherit;
+  font-size: 14px;
+  font-weight: 700;
+  cursor: pointer;
 }
 </style>