feat(web): add per-phone unarchive-thread toggle to settings

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: bf78429e-573c-406c-9f7c-1d6e1bddbbb5

Author: AchoArnold

web/app/pages/settings/index.vue

@@ -1688,6 +1688,15 @@ onMounted(async () => {
                   placeholder="We are currently closed at the moment, please send us a text message from 09:00 to 17:00"
                   hint="Here you can configure an automated SMS message which is sent to the caller when this phone has a missed call"
                 />
+                <VSwitch
+                  v-model="activePhone.unarchive_thread"
+                  class="mt-4"
+                  color="primary"
+                  density="compact"
+                  label="Unarchive thread on new message"
+                  hint="When a new message is received, move an archived conversation back to the inbox"
+                  persistent-hint
+                />
               </VCol>
             </VRow>
           </VContainer>