refactor: rename project references from tmux-mcp to voice-dev-mcp
Update internal references, package scripts, binary name, service identifiers, and tool descriptions to reflect the voice-dev branding. Changes default HTTP port from 3000 to 6767.
```
- Rename all packages from @realtime-voice/* to @voice-dev/*
- Update root package.json name and description
- Update README with new branding and remove monorepo terminology
- Rename GitHub repo to voice-dev
- Remove Vercel link to prepare for fresh deployment