* docs(rust): add doc comments to delta enums and fix dead_code warnings
Add missing documentation to ProtocolDelta, CoreDelta, and BridgeDelta
enum variants and their struct fields across the protocol, core, and
bridge crates. Document the ChannelId::ROOT constant and the
take_delta_rx adapter method.
Fix dead_code warnings:
- keyring_disabled: add #[cfg] gate matching its callers
- snapshot_signature: add #[cfg(test)] for future test use
* fix(rust): correct `order` field docs to predecessor channel ID, narrow audio engine cfg gates
- Correct `order` field documentation in ProtocolDelta, SessionEvent,
and BridgeEvent from 'sort order' to 'predecessor channel ID
(TeamSpeak linked-list ordering hint)' per Copilot review feedback.
- Narrow AudioEngine voice_out_tx, voice_activity_selector, and mic_gain
cfg gates from ios+macos+android to android-only, since these fields
are only read from self in android_restart_voice_unit. On iOS/macOS the
values are passed directly to the voice backend at construction time.
Edison Jwa
fb2a8e0a80