fix(tenancy): align columns and actions in merchant team table

- Fixed header/column alignment: Member | Role | Status | Actions
- Store count + chevron moved inline with member name (not a separate column)
- Role column shows single role, "Owner", or "Multiple roles" on main row
- Actions use fixed 4-slot grid (resend | view | edit | remove) ensuring
  icons always align vertically between main rows and sub-rows
- Empty slots render as blank space to maintain alignment

i18n: added multiple_roles key in 4 locales.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/tenancy/locales/en.json

@@ -53,6 +53,7 @@
         "personal_info": "Personal Information",
         "resend_invitation": "Resend Invitation",
         "save_profile": "Save Profile",
+        "multiple_roles": "Multiple roles",
         "view_member": "View Member",
         "account_information": "Account Information",
         "username": "Username",