plugin wid calls, core: implements WebRTC DataChannel file transfer: - Add a new "file" icon in call UI to send a file via WebRTC. - Handle new preflight mechanism, and WebRTC file transfer. - Native file chooser handling has been moved to new `core.file_chooser` module, and now supports "save" and "dir" modes (based on `plyer`). rel 442

[DEFAULT]
bridge = pb
log_level = debug
log_fmt = #[%%(levelname)s][%%(name)s] %%(message)s

[cagou]
no_certificate_validation = true
log_level = debug
log_fmt = [%%(levelname)s][%%(name)s] %%(message)s