feat(voice): inbox-level customizable WhatsApp call permission body

Surface inbox.provider_config['call_permission_request_body'] in the
WhatsappCallingPage settings as an editable textarea — saving submits the
new key alongside calling_enabled. Blank trims to null so the i18n default
keeps applying. Backend reads the override before the i18n fallback.

app/javascript/dashboard/i18n/locale/en/inboxMgmt.json

@@ -661,6 +661,11 @@
       "HOW_IT_WORKS": {
         "LABEL": "How it works",
         "DESCRIPTION": "Calls are placed peer-to-peer between the agent's browser and Meta — no extra credentials are required. Make sure the agent's browser has microphone permission for this site."
+      },
+      "PERMISSION_REQUEST_BODY": {
+        "LABEL": "Call permission request message",
+        "HELP_TEXT": "Shown to the contact when they haven't yet consented to receive calls. Leave blank to use the default.",
+        "PLACEHOLDER": "We would like to call you regarding your conversation."
       }
     },
     "CHANNEL_PREFERENCES": "Channel Preferences",

app/javascript/dashboard/routes/dashboard/settings/inbox/settingsPage/WhatsappCallingPage.vue

@@ -3,12 +3,14 @@ import { useAlert } from 'dashboard/composables';
 import SettingsFieldSection from 'dashboard/components-next/Settings/SettingsFieldSection.vue';
 import SettingsToggleSection from 'dashboard/components-next/Settings/SettingsToggleSection.vue';
 import NextButton from 'dashboard/components-next/button/Button.vue';
+import TextArea from 'next/textarea/TextArea.vue';
 
 export default {
   components: {
     SettingsFieldSection,
     SettingsToggleSection,
     NextButton,
+    TextArea,
   },
   props: {
     inbox: {
@@ -19,6 +21,8 @@ export default {
   data() {
     return {
       callingEnabled: this.inbox.provider_config?.calling_enabled || false,
+      permissionRequestBody:
+        this.inbox.provider_config?.call_permission_request_body || '',
       isUpdating: false,
     };
   },
@@ -33,6 +37,9 @@ export default {
     'inbox.provider_config.calling_enabled'(val) {
       this.callingEnabled = val || false;
     },
+    'inbox.provider_config.call_permission_request_body'(val) {
+      this.permissionRequestBody = val || '';
+    },
   },
   methods: {
     async updateCallingSettings() {
@@ -45,6 +52,8 @@ export default {
             provider_config: {
               ...this.inbox.provider_config,
               calling_enabled: this.callingEnabled,
+              call_permission_request_body:
+                this.permissionRequestBody.trim() || null,
             },
           },
         });
@@ -75,6 +84,22 @@ export default {
       <woot-code :script="phoneNumber" lang="html" />
     </SettingsFieldSection>
 
+    <SettingsFieldSection
+      :label="$t('INBOX_MGMT.WHATSAPP_CALLING.PERMISSION_REQUEST_BODY.LABEL')"
+      :help-text="
+        $t('INBOX_MGMT.WHATSAPP_CALLING.PERMISSION_REQUEST_BODY.HELP_TEXT')
+      "
+    >
+      <TextArea
+        v-model="permissionRequestBody"
+        :placeholder="
+          $t('INBOX_MGMT.WHATSAPP_CALLING.PERMISSION_REQUEST_BODY.PLACEHOLDER')
+        "
+        auto-height
+        resize
+      />
+    </SettingsFieldSection>
+
     <SettingsFieldSection
       :label="$t('INBOX_MGMT.WHATSAPP_CALLING.HOW_IT_WORKS.LABEL')"
       :help-text="$t('INBOX_MGMT.WHATSAPP_CALLING.HOW_IT_WORKS.DESCRIPTION')"