feat: event-driven UI updates for instant channel switching (#15)

* chore: regenerate Cargo.lock after rebase

* fix(ui): add 1s cool-down to prevent double-tap channel join

voiceJoin returns instantly (fire-and-forget protocol), so the
pending-join guard clears before a second tap lands. The cool-down
prevents the rapid channel oscillation and ClientIsFlooding (524)
that results from double-tapping.

* fix(ui): handle ChannelAlreadyIn as success, ClientIsFlooding with backoff

- ChannelAlreadyIn (0x0302): treat as silent success, update UI state
- ClientIsFlooding (0x020c): show localized snackbar, extend cooldown 5s
- Add l10n strings for flooding error (en + zh)

* fix(proto): use Windows TS3 client version for broadest compatibility

Matches Qint's default (Windows_3_X_X__1). Avoids server-side
behavioral differences with TS5 version strings.

* fix(proto): patch tsproto-types to handle short P-256 coordinates

BigInt::to_bytes_be() strips leading zeros, causing WrongPublicKeyLength
when a server's ephemeral key coordinate starts with 0x00. Patch from
EdisonJwa/tsclientlib fix/p256-short-coordinate-pad branch left-pads
coordinates to the P-256 field size instead of rejecting them.

* refactor(core): stop watchdog from emitting SnapshotChanged

The watchdog now serves only as a liveness probe (miss counting for
reconnection). UI updates are handled entirely by the event-driven
delta path (ProtocolDelta → SessionEvent → BridgeEvent → Flutter).

Removes signature tracking and SnapshotChanged emission from the
supervisor loop. The initial snapshot is still fetched via the
Connected event handler in Flutter.

* refactor(ui): remove channel-join cooldown guard

With event-driven deltas the UI updates instantly on channel moves,
so the 1-second cooldown is no longer needed. Double-taps are handled
by the server (ChannelAlreadyIn → success) and the pending-channel-id
guard prevents overlapping requests.

Also removes the _lastJoinCompletedAt field entirely.

* fix(core): reattach event forwarders after reconnect

The reconnect path swapped in a new ProtocolClient but never took
chat_rx, activity_rx, or delta_rx from it. After the first reconnect,
the event-driven UI pipeline was dead.

Fix by extracting spawn_event_forwarders() helper called on both
initial connect and reconnect. Also replaces lossy try_recv+sleep
polling with proper recv().await for push-based delivery.

* feat(protocol): enrich delta schema with all snapshot-visible fields

ClientJoined now carries input_muted, output_muted, is_server_query,
talk_power, talk_power_granted. ChannelAdded/ChannelUpdated now carry
has_password and needed_talk_power. ClientUpdated also carries
is_server_query, talk_power, talk_power_granted.

This prevents local snapshot drift where fabricated defaults could
hide password requirements, talk-power restrictions, or client type.

* refactor: remove dead SnapshotChanged variant end-to-end

SnapshotChanged is no longer emitted since the watchdog was refactored
to liveness-only. Removes the variant from SessionEvent, BridgeEvent,
and the Flutter switch statement. FRB bindings regenerated.

* fix(ci): regenerate license inventory and fix iOS submodule fetch

- Regenerate docs/security/license-inventory.md to match current lockfile
- Remove submodules: true from checkout (causes hard fail on private submodule)
- Add explicit git submodule update --init --depth=1 with || true fallback
- Check silero-coreml/Package.swift instead of directory existence

Cargo.toml

@@ -71,5 +71,14 @@ serde = { version = "1", features = ["derive"] }
 # pr2502/cmake-rs as of 2026-05-18) so the patch is reproducible.
 # Re-evaluate and remove once PR #257 merges and a fresh `cmake`
 # release lands on crates.io (current upstream is 0.7.2).
+# Patch tsproto-types to left-pad P-256 coordinates that are shorter than
+# 32 bytes.  BigInt::to_bytes_be() strips leading zero bytes; when a
+# coordinate happens to start with 0x00 (~0.8 % probability per coordinate)
+# the upstream code rejects it with WrongPublicKeyLength, breaking the
+# init-server handshake.  The fix zero-pads to the field size instead.
+# Fork: https://github.com/EdisonJwa/tsclientlib/tree/fix/p256-short-coordinate-pad
+[patch."https://github.com/ReSpeak/tsclientlib.git"]
+tsproto-types = { git = "https://github.com/EdisonJwa/tsclientlib.git", branch = "fix/p256-short-coordinate-pad" }
+
 [patch.crates-io]
 cmake = { git = "https://github.com/pr2502/cmake-rs", rev = "bdad5edc569d82151922c5c6c4685b1563f12aa1" }