This PR improves the voice call creation flow by simplifying
configuration and automating setup with Twilio APIs.
references: #11602 , #11481
## Key changes
- Removed the requirement for twiml_app_sid – provisioning is now
automated through APIs.
- Auto-configured webhook URLs for:
- Voice number callbacks
- Status callbacks
- twiML callbacks
- Disabled business hours, help center, and related options until voice
inbox is fully supported.
- Added a configuration tab in the voice inbox to display the required
Twilio URLs (to make verification easier in Twilio console).
## Test Cases
- Provisioning
- Create a new voice inbox → verify that Twilio app provisioning happens
automatically.
- Verify twiML callback
- Webhook configuration
- Check that both voice number callback and status callback URLs are
auto-populated in Twilio.
- Disabled features
- Confirm that business hours and help center options are
hidden/disabled for voice inbox.
- Configuration tab
- Open the voice inbox configuration tab → verify that the displayed
Twilio URLs match what’s set in Twilio.
