## 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
