feat: add per-inbox toggle to disable incoming calls (#14645)

## Description

Adds a per-inbox "Allow incoming calls" toggle for voice-enabled
WhatsApp and Twilio inboxes. When turned off, the setting is persisted
on the channel; actually rejecting inbound calls is handled in a
follow-up PR.

## Type of change

- [ ] New feature (non-breaking change which adds functionality)

## Screenshot
<img width="804" height="384" alt="Screenshot 2026-06-04 at 11 44 07 AM"
src="https://github.com/user-attachments/assets/df8bb026-0387-4031-bcba-6d9a56872eb7"
/>


## Checklist:

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

enterprise/app/controllers/enterprise/api/v1/accounts/inboxes_controller.rb

@@ -1,4 +1,6 @@
 module Enterprise::Api::V1::Accounts::InboxesController
+  extend ActiveSupport::Concern
+
   def inbox_attributes
     super + ee_inbox_attributes
   end
@@ -21,6 +23,24 @@ module Enterprise::Api::V1::Accounts::InboxesController
     render_could_not_create_error(e.message)
   end
 
+  # Toggles only the inbound-calls flag in provider_config. Saved with validate: false
+  # so WhatsApp's remote credential re-check (validate_provider_config) can't reject a
+  # simple toggle, mirroring enable_voice_calling!. Voice support (WhatsApp calling or
+  # Twilio voice) is guarded inline by ensure_inbound_calls_supported.
+  def set_inbound_calls
+    return unless ensure_inbound_calls_supported
+
+    channel = @inbox.channel
+    channel.provider_config = (channel.provider_config || {}).merge(
+      'inbound_calls_enabled' => ActiveModel::Type::Boolean.new.cast(params[:inbound_calls_enabled])
+    )
+    channel.save!(validate: false)
+    @inbox.update_account_cache # bump inbox cache key so the cached inbox list refetches the new flag
+    head :ok
+  rescue StandardError => e
+    render_could_not_create_error(e.message)
+  end
+
   def ee_inbox_attributes
     [auto_assignment_config: [:max_assignment_limit]]
   end
@@ -35,6 +55,14 @@ module Enterprise::Api::V1::Accounts::InboxesController
     false
   end
 
+  # Inbound calls can be toggled on any voice-enabled inbox (WhatsApp calling or Twilio voice).
+  def ensure_inbound_calls_supported
+    return true if @inbox.channel.try(:voice_enabled?)
+
+    render_could_not_create_error('Inbox does not support calling')
+    false
+  end
+
   def allowed_channel_types
     super + ['voice']
   end

enterprise/app/controllers/twilio/voice_controller.rb

@@ -24,6 +24,8 @@ class Twilio::VoiceController < ApplicationController
       "TWILIO_VOICE_TWIML account=#{current_account.id} call_sid=#{twilio_call_sid} from=#{twilio_from} direction=#{twilio_direction}"
     )
 
+    return render xml: reject_twiml if reject_inbound?
+
     call = resolve_call
     render xml: conference_twiml(call)
   end
@@ -88,6 +90,16 @@ class Twilio::VoiceController < ApplicationController
     from_number.start_with?('client:')
   end
 
+  # A fresh contact-initiated leg on an inbox with inbound calls turned off.
+  # Reject it so no conference, conversation, or Call row is created.
+  def reject_inbound?
+    twilio_direction == 'inbound' && !agent_leg?(twilio_from) && !inbox.channel.inbound_calls_enabled?
+  end
+
+  def reject_twiml
+    Twilio::TwiML::VoiceResponse.new(&:reject).to_s
+  end
+
   def resolve_call
     return find_call_for_agent if agent_leg?(twilio_from)
 

enterprise/app/services/whatsapp/incoming_call_service.rb

@@ -72,6 +72,12 @@ class Whatsapp::IncomingCallService
   end
 
   def create_inbound_call(payload)
+    unless inbox.channel.inbound_calls_enabled?
+      Rails.logger.info "[WHATSAPP CALL] Inbound calls disabled for inbox #{inbox.id}; rejecting call #{payload[:id]}"
+      inbox.channel.provider_service.reject_call(payload[:id])
+      return
+    end
+
     sdp_offer = payload.dig(:session, :sdp)
     extra_meta = { 'sdp_offer' => sdp_offer, 'ice_servers' => Call.default_ice_servers }
     name = caller_profile_name(payload)