## Linear Ticket
https://linear.app/chatwoot/issue/CW-7264/add-mute-button-in-twilio-calls
## Description
Adds mute support for Twilio voice calls. Previously the mute button was
shown only for WhatsApp calls (which toggle the local mic track in the
browser), so Twilio calls had no way to mute. The call widget now routes
mute by provider: WhatsApp continues to toggle the local mic track,
while Twilio uses the Voice SDK connection's native `mute()`. The mute
button is now shown for any active call, and unmute works symmetrically.
## Type of change
- [x] New feature (non-breaking change which adds functionality)
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [x] I have made corresponding changes to the documentation
- [x] 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
Twilio voice now uses first-class `Call` records as the source of truth
for call state, instead of storing it on
`conversation.additional_attributes` and `conversation.identifier`. Each
call gets its own record, its own `voice_call` bubble matched by
`call_sid`, and its own conference name keyed off `Call.id`. Multiple
calls on the same conversation (for `lock_to_single_conversation`
inboxes) now work correctly, and the conversation card stays in sync
with the real latest message.
Fixes https://linear.app/chatwoot/issue/PLA-121/lock-to-single-thread
---------
Co-authored-by: Muhsin <12408980+muhsin-k@users.noreply.github.com>
