fix(desktop): resolve Tauri state panic on startup

SessionStreamGuard and StreamCancelFlags were type aliases to the same
Arc<DashMap<String, Arc<AtomicBool>>> type. Tauri distinguishes managed
state by Rust type, so registering both caused a runtime panic:
"state for type ... is already being managed".

Changed to newtype structs with Deref impl to the inner Arc<DashMap>,
keeping all call sites compatible without changes.

desktop/src-tauri/src/kernel_commands/mod.rs

@@ -34,12 +34,28 @@ pub type SchedulerState = Arc<Mutex<Option<zclaw_kernel::scheduler::SchedulerSer
 /// for the same session_id.
 /// Uses `AtomicBool` so the `DashMap` — `true` means active stream, `false` means idle.
 /// The `spawn`ed task resets the flag on completion/error.
-pub type SessionStreamGuard = Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>;
+///
+/// Newtype wrapper is required because Tauri state management uses the Rust type
+/// system to distinguish states — two `type` aliases to the same underlying type
+/// would cause a runtime panic ("state already being managed").
+#[derive(Clone, Default)]
+pub struct SessionStreamGuard(pub Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>);
 
 /// Per-session stream cancellation flags.
 /// When a user cancels a stream, the flag for that session_id is set to `true`.
 /// The spawned `agent_chat_stream` task checks this flag each iteration.
-pub type StreamCancelFlags = Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>;
+#[derive(Clone, Default)]
+pub struct StreamCancelFlags(pub Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>);
+
+impl std::ops::Deref for SessionStreamGuard {
+    type Target = Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>;
+    fn deref(&self) -> &Self::Target { &self.0 }
+}
+
+impl std::ops::Deref for StreamCancelFlags {
+    type Target = Arc<dashmap::DashMap<String, Arc<std::sync::atomic::AtomicBool>>>;
+    fn deref(&self) -> &Self::Target { &self.0 }
+}
 
 // ---------------------------------------------------------------------------
 // Shared validation helpers