chore(voice): unprivate voice provider packages (#2066)

The voice provider packages carry "private": true, so changesets versions
them and writes their changelogs while changeset publish skips them. Plivo
is bumped to 0.1.0 by the pending release yet has never reached npm, and
the Deepgram, ElevenLabs, and AssemblyAI install instructions in the public
docs reference packages that do not exist.

Telnyx is the only provider already publishing, because its private field
was removed by hand in 2142b23.

Publishing still requires npm-side bootstrap: trusted publishing cannot
create a package's first version, and four of these five names are absent
from the registry.

Author: cjol

voice-providers/assemblyai/package.json

@@ -1,6 +1,5 @@
 {
   "name": "@cloudflare/voice-assemblyai",
-  "private": true,
   "version": "0.0.2",
   "description": "AssemblyAI Universal 3.5 Pro Realtime STT provider for Cloudflare Agents voice pipeline",
   "repository": {

voice-providers/deepgram/package.json

@@ -1,6 +1,5 @@
 {
   "name": "@cloudflare/voice-deepgram",
-  "private": true,
   "version": "0.0.1",
   "description": "Deepgram streaming STT provider for Cloudflare Agents voice pipeline",
   "repository": {

voice-providers/elevenlabs/package.json

@@ -1,6 +1,5 @@
 {
   "name": "@cloudflare/voice-elevenlabs",
-  "private": true,
   "version": "0.0.2",
   "description": "ElevenLabs STT and TTS providers for Cloudflare Agents voice pipeline",
   "repository": {

voice-providers/plivo/package.json

@@ -1,6 +1,5 @@
 {
   "name": "@cloudflare/voice-plivo",
-  "private": true,
   "version": "0.0.1",
   "description": "Plivo audio streaming adapter for Cloudflare Agents voice pipeline — connect phone calls to VoiceAgent",
   "repository": {

voice-providers/twilio/package.json

@@ -1,6 +1,5 @@
 {
   "name": "@cloudflare/voice-twilio",
-  "private": true,
   "version": "0.0.2",
   "description": "Twilio Media Streams adapter for Cloudflare Agents voice pipeline — connect phone calls to VoiceAgent",
   "repository": {