refactor(auth): centralize role checks into utility

Removed direct user role string checks and replaced with type-safe utils.

app/pages/operator/reports/[id].vue

@@ -129,7 +129,9 @@ const handleStatusUpdate = async () => {
 }
 
 const handleAssignTeam = async () => {
+  if (isAdmin(user.value?.role)) return
   if (!selectedTeamId.value) return
+
   isAssigning.value = true
   try {
     const res = await assignTeam(reportId, {
@@ -229,6 +231,8 @@ const handleSendMessage = async (msgText: string, files: File[]) => {
 
 const canFlagMessage = (message: Message) => {
   if (!user.value) return false
+  if (isAdmin(user.value?.role)) return false
+
   const isCitizenMessage = message.user_id !== user.value.id && message.user_id === report.value?.user_id
   const isAlreadyFlagged = flaggedMessageIds.value.includes(message.id)
   return isCitizenMessage && !isAlreadyFlagged
@@ -408,7 +412,7 @@ const formattedInterventionLinkExpiry = computed(() =>
                   </p>
                 </div>
               </div>
-              <div class="card-body pt-0">
+              <div v-if="!isAdmin(user?.role)" class="card-body pt-0">
                 <button class="btn btn-outline-primary w-100" @click="isAssignModalOpen = true" :disabled="teams.length === 0">
                   Assegna team
                 </button>