Add multi-branch POS with team roles and branch-scoped cashiers.

Pro and Business users can manage branches, invite cashiers with branch assignment, and switch registers; sales and register flows respect acting location.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Models/User.php

@@ -37,18 +37,38 @@ class User extends Authenticatable
             ->where('status', QrTeamMember::STATUS_ACTIVE);
     }
 
+    public function posMemberships(): HasMany
+    {
+        return $this->hasMany(PosMember::class, 'user_ref', 'public_id');
+    }
+
     public function canAccessAccount(int $accountId): bool
     {
-        return $accountId === $this->id
-            || $this->memberships()->where('account_id', $accountId)->exists();
+        if ($accountId === $this->id) {
+            return true;
+        }
+
+        if ($this->memberships()->where('account_id', $accountId)->exists()) {
+            return true;
+        }
+
+        $account = self::find($accountId);
+
+        return $account !== null
+            && $this->posMemberships()->where('owner_ref', $account->public_id)->exists();
     }
 
     /** @return Collection<int, User> */
     public function accessibleAccounts(): Collection
     {
-        $ids = $this->memberships()->pluck('account_id')->all();
+        $qrIds = $this->memberships()->pluck('account_id')->all();
+        $posOwnerRefs = $this->posMemberships()->pluck('owner_ref')->all();
 
-        return collect([$this])->merge(self::whereIn('id', $ids)->get())->unique('id')->values();
+        return collect([$this])
+            ->merge(self::whereIn('id', $qrIds)->get())
+            ->merge(self::whereIn('public_id', $posOwnerRefs)->get())
+            ->unique('id')
+            ->values();
     }
 
     public function avatarUrl(): ?string