Twilio now handles only the in-browser dial pad (Access Token + browser-Device outbound TwiML); Telnyx takes over SMS, inbound voicemail, the AI voice conversation loop, and staff-triggered outbound calls via TeXML. Adds TelnyxSettings model, Communication.provider discriminator, new comms/routes modules, and a real Telnyx Settings page. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>