feat: DeerFlow 2.0 core capabilities — Phase 1.0 + 1.1

Phase 1.0 — Butler Mode UI:
- Hide "自动化" and "技能市场" entries from sidebar navigation
- Remove AutomationPanel and SkillMarket view rendering from App.tsx
- Simplify MainViewType to only 'chat'
- Main interface is now: chat + conversation list + detail panel only

Phase 1.1 — Mode Differentiation:
- Add subagent_enabled field to ChatModeConfig (Rust), StreamChatRequest (Tauri),
  gateway-client, kernel-client, saas-relay-client, and streamStore
- TaskTool is now only registered when subagent_enabled=true (Ultra mode)
- System prompt includes sub-agent delegation instructions only in Ultra mode
- Frontend transmits subagent_enabled from ChatMode config through the full stack

This connects the 4-tier mode selector (Flash/Thinking/Pro/Ultra) to actual
backend behavioral differences — Ultra mode now truly enables sub-agent delegation.

crates/zclaw-kernel/src/kernel/messaging.rs

@@ -4,12 +4,13 @@ use tokio::sync::mpsc;
 use zclaw_types::{AgentId, Result};
 
 /// Chat mode configuration passed from the frontend.
-/// Controls thinking, reasoning, and plan mode behavior.
+/// Controls thinking, reasoning, plan mode, and sub-agent behavior.
 #[derive(Debug, Clone)]
 pub struct ChatModeConfig {
     pub thinking_enabled: Option<bool>,
     pub reasoning_effort: Option<String>,
     pub plan_mode: Option<bool>,
+    pub subagent_enabled: Option<bool>,
 }
 
 use zclaw_runtime::{AgentLoop, tool::builtin::PathValidator};
@@ -45,7 +46,8 @@ impl Kernel {
         let model = self.config.model().to_string();
 
         // Create agent loop with model configuration
-        let tools = self.create_tool_registry();
+        let subagent_enabled = chat_mode.as_ref().and_then(|m| m.subagent_enabled).unwrap_or(false);
+        let tools = self.create_tool_registry(subagent_enabled);
         let mut loop_runner = AgentLoop::new(
             *agent_id,
             self.driver.clone(),
@@ -92,7 +94,10 @@ impl Kernel {
         }
 
         // Build system prompt with skill information injected
-        let system_prompt = self.build_system_prompt_with_skills(agent_config.system_prompt.as_ref()).await;
+        let system_prompt = self.build_system_prompt_with_skills(
+            agent_config.system_prompt.as_ref(),
+            subagent_enabled,
+        ).await;
         let loop_runner = loop_runner.with_system_prompt(&system_prompt);
 
         // Run the loop
@@ -147,7 +152,8 @@ impl Kernel {
         let model = self.config.model().to_string();
 
         // Create agent loop with model configuration
-        let tools = self.create_tool_registry();
+        let subagent_enabled = chat_mode.as_ref().and_then(|m| m.subagent_enabled).unwrap_or(false);
+        let tools = self.create_tool_registry(subagent_enabled);
         let mut loop_runner = AgentLoop::new(
             *agent_id,
             self.driver.clone(),
@@ -197,7 +203,10 @@ impl Kernel {
         // Use external prompt if provided, otherwise build default
         let system_prompt = match system_prompt_override {
             Some(prompt) => prompt,
-            None => self.build_system_prompt_with_skills(agent_config.system_prompt.as_ref()).await,
+            None => self.build_system_prompt_with_skills(
+                agent_config.system_prompt.as_ref(),
+                subagent_enabled,
+            ).await,
         };
         let loop_runner = loop_runner.with_system_prompt(&system_prompt);
 
@@ -206,8 +215,13 @@ impl Kernel {
         loop_runner.run_streaming(session_id, message).await
     }
 
-    /// Build a system prompt with skill information injected
-    pub(super) async fn build_system_prompt_with_skills(&self, base_prompt: Option<&String>) -> String {
+    /// Build a system prompt with skill information injected.
+    /// When `subagent_enabled` is true, adds sub-agent delegation instructions.
+    pub(super) async fn build_system_prompt_with_skills(
+        &self,
+        base_prompt: Option<&String>,
+        subagent_enabled: bool,
+    ) -> String {
         // Get skill list asynchronously
         let skills = self.skills.list().await;
 
@@ -215,7 +229,8 @@ impl Kernel {
             .map(|p| p.clone())
             .unwrap_or_else(|| "You are a helpful AI assistant.".to_string());
 
-        // Inject skill information with categories
+        // Inject skill metadata only (progressive loading pattern from DeerFlow).
+        // Full skill content is loaded on-demand via `load_skill_content` tool.
         if !skills.is_empty() {
             prompt.push_str("\n\n## Available Skills\n\n");
             prompt.push_str("You have access to specialized skills. Analyze user intent and autonomously call `execute_skill` with the appropriate skill_id.\n\n");
@@ -245,6 +260,21 @@ impl Kernel {
             prompt.push_str("User: \"分析腾讯财报\" → Intent: Financial analysis → Call: execute_skill(\"finance-tracker\", {...})\n");
         }
 
+        // Sub-agent delegation instructions (Ultra mode only)
+        if subagent_enabled {
+            prompt.push_str("\n\n## Sub-Agent Delegation\n\n");
+            prompt.push_str("You can delegate complex sub-tasks to sub-agents using the `task` tool. This enables parallel execution of independent work.\n\n");
+            prompt.push_str("### When to use sub-agents:\n");
+            prompt.push_str("- Complex tasks that can be decomposed into independent parallel sub-tasks\n");
+            prompt.push_str("- Research tasks requiring multiple independent searches\n");
+            prompt.push_str("- Tasks requiring different expertise areas simultaneously\n\n");
+            prompt.push_str("### Guidelines:\n");
+            prompt.push_str("- Break complex work into clear, self-contained sub-tasks\n");
+            prompt.push_str("- Each sub-task should have a clear objective and expected output\n");
+            prompt.push_str("- Synthesize sub-agent results into a coherent final response\n");
+            prompt.push_str("- Maximum 3 concurrent sub-agents — batch if more are needed\n");
+        }
+
         prompt
     }
 

crates/zclaw-kernel/src/kernel/mod.rs

@@ -162,18 +162,22 @@ impl Kernel {
         })
     }
 
-    /// Create a tool registry with built-in tools
-    pub(crate) fn create_tool_registry(&self) -> ToolRegistry {
+    /// Create a tool registry with built-in tools.
+    /// When `subagent_enabled` is false, TaskTool is excluded to prevent
+    /// the LLM from attempting sub-agent delegation in non-Ultra modes.
+    pub(crate) fn create_tool_registry(&self, subagent_enabled: bool) -> ToolRegistry {
         let mut tools = ToolRegistry::new();
         zclaw_runtime::tool::builtin::register_builtin_tools(&mut tools);
 
-        // Register TaskTool with driver and memory for sub-agent delegation
-        let task_tool = zclaw_runtime::tool::builtin::TaskTool::new(
-            self.driver.clone(),
-            self.memory.clone(),
-            self.config.model(),
-        );
-        tools.register(Box::new(task_tool));
+        // Register TaskTool only when sub-agent mode is enabled (Ultra mode)
+        if subagent_enabled {
+            let task_tool = zclaw_runtime::tool::builtin::TaskTool::new(
+                self.driver.clone(),
+                self.memory.clone(),
+                self.config.model(),
+            );
+            tools.register(Box::new(task_tool));
+        }
 
         tools
     }