refactor(desktop): split kernel_commands/pipeline_commands into modules, add SaaS client libs and gateway modules

Split monolithic kernel_commands.rs (2185 lines) and pipeline_commands.rs (1391 lines)
into focused sub-modules under kernel_commands/ and pipeline_commands/ directories.
Add gateway module (commands, config, io, runtime), health_check, and 15 new
TypeScript client libraries for SaaS relay, auth, admin, telemetry, and kernel
sub-systems (a2a, agent, chat, hands, skills, triggers).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/src-tauri/src/kernel_commands/a2a.rs

@@ -0,0 +1,114 @@
+//! A2A (Agent-to-Agent) commands — gated behind `multi-agent` feature
+
+use serde_json;
+use tauri::State;
+use zclaw_types::AgentId;
+
+use super::KernelState;
+
+// ============================================================
+// A2A (Agent-to-Agent) Commands — gated behind multi-agent feature
+// ============================================================
+
+#[cfg(feature = "multi-agent")]
+/// Send a direct A2A message from one agent to another
+#[tauri::command]
+pub async fn agent_a2a_send(
+    state: State<'_, KernelState>,
+    from: String,
+    to: String,
+    payload: serde_json::Value,
+    message_type: Option<String>,
+) -> Result<(), String> {
+    let kernel_lock = state.lock().await;
+    let kernel = kernel_lock.as_ref()
+        .ok_or_else(|| "Kernel not initialized. Call kernel_init first.".to_string())?;
+
+    let from_id: AgentId = from.parse()
+        .map_err(|_| format!("Invalid from agent ID: {}", from))?;
+    let to_id: AgentId = to.parse()
+        .map_err(|_| format!("Invalid to agent ID: {}", to))?;
+
+    let msg_type = message_type.map(|mt| match mt.as_str() {
+        "request" => zclaw_kernel::A2aMessageType::Request,
+        "notification" => zclaw_kernel::A2aMessageType::Notification,
+        "task" => zclaw_kernel::A2aMessageType::Task,
+        _ => zclaw_kernel::A2aMessageType::Notification,
+    });
+
+    kernel.a2a_send(&from_id, &to_id, payload, msg_type).await
+        .map_err(|e| format!("A2A send failed: {}", e))?;
+
+    Ok(())
+}
+
+/// Broadcast a message from one agent to all other agents
+#[cfg(feature = "multi-agent")]
+#[tauri::command]
+pub async fn agent_a2a_broadcast(
+    state: State<'_, KernelState>,
+    from: String,
+    payload: serde_json::Value,
+) -> Result<(), String> {
+    let kernel_lock = state.lock().await;
+    let kernel = kernel_lock.as_ref()
+        .ok_or_else(|| "Kernel not initialized. Call kernel_init first.".to_string())?;
+
+    let from_id: AgentId = from.parse()
+        .map_err(|_| format!("Invalid from agent ID: {}", from))?;
+
+    kernel.a2a_broadcast(&from_id, payload).await
+        .map_err(|e| format!("A2A broadcast failed: {}", e))?;
+
+    Ok(())
+}
+
+/// Discover agents with a specific capability
+#[cfg(feature = "multi-agent")]
+#[tauri::command]
+pub async fn agent_a2a_discover(
+    state: State<'_, KernelState>,
+    capability: String,
+) -> Result<Vec<serde_json::Value>, String> {
+    let kernel_lock = state.lock().await;
+    let kernel = kernel_lock.as_ref()
+        .ok_or_else(|| "Kernel not initialized. Call kernel_init first.".to_string())?;
+
+    let profiles = kernel.a2a_discover(&capability).await
+        .map_err(|e| format!("A2A discover failed: {}", e))?;
+
+    let result: Vec<serde_json::Value> = profiles.iter()
+        .filter_map(|p| serde_json::to_value(p).ok())
+        .collect();
+
+    Ok(result)
+  }
+
+/// Delegate a task to another agent and wait for response
+#[cfg(feature = "multi-agent")]
+#[tauri::command]
+pub async fn agent_a2a_delegate_task(
+    state: State<'_, KernelState>,
+    from: String,
+    to: String,
+    task: String,
+    timeout_ms: Option<u64>,
+) -> Result<serde_json::Value, String> {
+    let kernel_lock = state.lock().await;
+    let kernel = kernel_lock.as_ref()
+        .ok_or_else(|| "Kernel not initialized. Call kernel_init first.".to_string())?;
+
+    let from_id: AgentId = from.parse()
+        .map_err(|_| format!("Invalid from agent ID: {}", from))?;
+    let to_id: AgentId = to.parse()
+        .map_err(|_| format!("Invalid to agent ID: {}", to))?;
+
+    let timeout = timeout_ms.unwrap_or(30_000);
+
+ // 30 seconds default
+
+    let response = kernel.a2a_delegate_task(&from_id, &to_id, task, timeout).await
+        .map_err(|e| format!("A2A task delegation failed: {}", e))?;
+
+    Ok(response)
+  }