feat(protocol): per-platform TS3 client_version selection

ConnectOptions previously took tsclientlib's default Version. Servers that
strictly check the announced client signature could refuse or downgrade
those sessions. Add pick_client_version() that selects a stable signed
descriptor matching the runtime OS:

  Windows  -> Version::Windows_5_0_0_beta51
  Linux    -> Version::Linux_5_0_0_beta51
  macOS    -> Version::macOS_5_0_0_beta51
  Android  -> Version::Android_3_5_0__7
  iOS      -> Version::iOS_3_5_6
  other    -> Linux fallback

All five variants are guaranteed to exist in the vendored tsproto-types
enum at compile time; build fails loudly if upstream removes one.

Wired into Connection::build(...).version(pick_client_version()) on every
connect. Emits 'selected TS3 client_version' info log line so the choice
is visible in chanora.log.

crates/chanora_protocol/src/adapter.rs

@@ -28,13 +28,68 @@ use tsclientlib::data::{self, Channel, Client};
 use tsclientlib::prelude::*;
 use tsclientlib::{
     ChannelId as TsChannelId, Connection, DisconnectOptions, Identity, MessageHandle,
-    OutCommandExt, StreamItem,
+    OutCommandExt, StreamItem, Version,
 };
 use tsproto_packets::packets::{InAudioBuf, OutPacket};
 
 use crate::dto::{ChannelId, ChannelInfo, ClientId, ClientInfo, ServerSnapshot};
 use crate::ProtocolError;
 
+/// Pick the TeamSpeak `client_version`/platform/signature triple
+/// (sourced from `ReSpeak/tsdeclarations/Versions.csv`, baked into
+/// `tsproto-types` at vendor-time) that best matches the *runtime*
+/// platform Chanora is executing on.
+///
+/// Per-platform selection (set by the project owner):
+///
+///   * Windows / Linux / macOS desktops announce as TeamSpeak **5
+///     beta51** — the latest TS5 desktop signature in the vendored
+///     `tsproto-types` enum. TS5 servers expect this shape; TS3
+///     servers are happy to accept any well-formed signed client
+///     descriptor and have no codec-version coupling.
+///   * Android announces as **3.5.0__7** (the latest Android
+///     signature in the vendored enum).
+///   * iOS announces as **3.5.6** (latest iOS signature in the
+///     vendored enum).
+///
+/// All five variants are guaranteed to exist in the generated
+/// `Version` enum at compile time; if upstream rotates the CSV the
+/// build will fail loudly here rather than silently fall back.
+fn pick_client_version() -> Version {
+    #[cfg(target_os = "windows")]
+    {
+        Version::Windows_5_0_0_beta51
+    }
+    #[cfg(target_os = "macos")]
+    {
+        Version::macOS_5_0_0_beta51
+    }
+    #[cfg(target_os = "ios")]
+    {
+        Version::iOS_3_5_6
+    }
+    #[cfg(target_os = "android")]
+    {
+        Version::Android_3_5_0__7
+    }
+    #[cfg(target_os = "linux")]
+    {
+        Version::Linux_5_0_0_beta51
+    }
+    #[cfg(not(any(
+        target_os = "windows",
+        target_os = "macos",
+        target_os = "ios",
+        target_os = "android",
+        target_os = "linux"
+    )))]
+    {
+        // Last-ditch fallback for unanticipated targets (BSDs,
+        // Solaris-likes). Linux signature is the closest analogue.
+        Version::Linux_5_0_0_beta51
+    }
+}
+
 /// Typed configuration for a connection attempt.
 #[derive(Debug, Clone)]
 pub struct ConnectConfig {
@@ -331,7 +386,15 @@ async fn connection_task(
     // Pass the resolved SocketAddr directly to tsclientlib so it
     // skips its own resolver entirely (tsclientlib accepts
     // SocketAddr via the From<SocketAddr> for ServerAddress impl).
-    let mut builder = Connection::build(resolved).name(cfg.nickname.clone());
+    let client_version = pick_client_version();
+    info!(
+        target: "chanora_protocol",
+        client_version = %client_version,
+        "selected TS3 client_version for this platform"
+    );
+    let mut builder = Connection::build(resolved)
+        .name(cfg.nickname.clone())
+        .version(client_version);
 
     let identity = match cfg.identity.as_deref() {
         Some(s) => match Identity::new_from_str(s) {