feat: Optimize TODO_LIST structure with hierarchical display and container task handling

- Replace separate Main Tasks/Subtasks sections with unified hierarchical list
- Use ▸ symbol for container tasks (with subtasks) instead of checkboxes
- Maintain standard - [ ]/- [x] for executable leaf tasks
- Add 2-space indentation to show task hierarchy clearly
- Include status legend for better user understanding

Benefits:
- Eliminates confusion about non-executable main tasks
- Provides clear visual hierarchy in single list
- Reduces TODO_LIST complexity and improves usability
- Aligns container task concept with execution model

🤖 Generated with [Claude Code](https://claude.ai/code)

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

.claude/agents/code-developer.md

@@ -122,14 +122,18 @@ ELIF context insufficient OR task has analysis marker:
    ```markdown
    # Tasks: User Authentication System
    
-   ## Main Tasks
-   - [x] **IMPL-001**: Create auth module → [📋](./.task/impl-001.json) | [✅](./.summaries/IMPL-001.md)
+   ## Task Progress
+   ▸ **IMPL-001**: Create auth module → [📋](./.task/impl-001.json)
+     - [x] **IMPL-001.1**: Database schema → [📋](./.task/impl-001.1.json) | [✅](./.summaries/IMPL-001.1.md)
+     - [ ] **IMPL-001.2**: API endpoints → [📋](./.task/impl-001.2.json)
+   
    - [ ] **IMPL-002**: Add JWT validation → [📋](./.task/impl-002.json)
    - [ ] **IMPL-003**: OAuth2 integration → [📋](./.task/impl-003.json)
    
-   ## Subtasks
-   - [x] **IMPL-001.1**: Database schema → [📋](./.task/impl-001.1.json) | [✅](./.summaries/IMPL-001.1.md)
-   - [ ] **IMPL-001.2**: API endpoints → [📋](./.task/impl-001.2.json)
+   ## Status Legend
+   - `▸` = Container task (has subtasks)
+   - `- [ ]` = Pending leaf task
+   - `- [x]` = Completed leaf task
    ```
 
 3. **Generate Summary** (using session context paths):

.claude/commands/task/breakdown.md

@@ -73,10 +73,11 @@ Accept task breakdown? (y/n/edit): y
 Automatic generation:
 ```
 ✅ Task impl-1 broken down:
-├── impl-1.1: Design authentication schema
-├── impl-1.2: Implement core auth logic
-├── impl-1.3: Add security middleware
-└── impl-1.4: Write comprehensive tests
+▸ impl-1: Build authentication module (container)
+  ├── impl-1.1: Design authentication schema
+  ├── impl-1.2: Implement core auth logic
+  ├── impl-1.3: Add security middleware
+  └── impl-1.4: Write comprehensive tests
 
 Agents assigned:
 - impl-1.1 → planning-agent
@@ -85,6 +86,7 @@ Agents assigned:
 - impl-1.4 → code-review-test-agent
 
 JSON files created:
+- .task/impl-1.json (container)
 - .task/impl-1.1.json
 - .task/impl-1.2.json
 - .task/impl-1.3.json
@@ -267,11 +269,11 @@ Based on subtask type and implementation complexity:
 /task:breakdown impl-1
 
 Result:
-impl-1: Build authentication (container)
-├── impl-1.1: Design auth schema
-├── impl-1.2: Implement auth logic  
-├── impl-1.3: Add security middleware
-└── impl-1.4: Write tests
+▸ impl-1: Build authentication (container)
+  ├── impl-1.1: Design auth schema
+  ├── impl-1.2: Implement auth logic  
+  ├── impl-1.3: Add security middleware
+  └── impl-1.4: Write tests
 ```
 
 ### Two-Level Breakdown
@@ -279,13 +281,13 @@ impl-1: Build authentication (container)
 /task:breakdown impl-1 --depth=2
 
 Result:  
-impl-1: E-commerce checkout (container)
-├── impl-1.1: Payment processing
-│   ├── impl-1.1.1: Integrate gateway
-│   └── impl-1.1.2: Handle transactions
-├── impl-1.2: Order management
-│   └── impl-1.2.1: Create order model
-└── impl-1.3: Testing
+▸ impl-1: E-commerce checkout (container)
+  ├── impl-1.1: Payment processing
+  │   ├── impl-1.1.1: Integrate gateway
+  │   └── impl-1.1.2: Handle transactions
+  ├── impl-1.2: Order management
+  │   └── impl-1.2.1: Create order model
+  └── impl-1.3: Testing
 ```
 
 ## Error Handling

.claude/commands/workflow/plan.md

@@ -90,6 +90,7 @@ The command automatically detects input type:
 ### Task Generation
 - Automatically creates .task/ files when complexity warrants
 - Generates hierarchical task structure (max 3 levels)
+- Main tasks with subtasks become container tasks (not directly executable)
 - Updates session state with task references
 - Runs project structure analysis to populate paths field
 
@@ -191,6 +192,12 @@ task.paths = join(relevant_paths, ";")
 ### Optional TODO_LIST.md (Auto-triggered)
 Created when complexity > simple or task count > 5
 
+**TODO_LIST Structure**: Uses unified hierarchical list format
+- Container tasks (with subtasks) marked with `▸` symbol
+- Leaf tasks use standard `- [ ]` / `- [x]` checkboxes
+- Indentation shows hierarchy (2 spaces per level)
+- Container tasks represent logical grouping, not executable items
+
 ### Task JSON Files (Auto-created)
 Generated in .task/ directory when decomposition enabled
 

.claude/workflows/workflow-architecture.md

@@ -384,17 +384,25 @@ File structure scales with task complexity to minimize overhead for simple tasks
 ```markdown
 # Tasks: [Session Topic]
 
-## Main Tasks
-- [ ] **IMPL-001**: [Task Description] → [📋](./.task/impl-001.json)
-- [x] **IMPL-002**: [Completed Task] → [📋](./.task/impl-002.json) | [✅](./.summaries/IMPL-002.md)
-- [ ] **IMPL-003**: [Task Description] → [📋](./.task/impl-003.json)
+## Task Progress
+▸ **IMPL-001**: [Main Task Group] → [📋](./.task/impl-001.json)
+  - [ ] **IMPL-001.1**: [Subtask] → [📋](./.task/impl-001.1.json)
+  - [x] **IMPL-001.2**: [Subtask] → [📋](./.task/impl-001.2.json) | [✅](./.summaries/IMPL-001.2.md)
+  
+- [x] **IMPL-002**: [Simple Task] → [📋](./.task/impl-002.json) | [✅](./.summaries/IMPL-002.md)
 
-## Subtasks  
-- [ ] **IMPL-001.1**: [Subtask] → [📋](./.task/impl-001.1.json)
-- [ ] **IMPL-001.2**: [Subtask] → [📋](./.task/impl-001.2.json)
+▸ **IMPL-003**: [Main Task Group] → [📋](./.task/impl-003.json)
+  - [ ] **IMPL-003.1**: [Subtask] → [📋](./.task/impl-003.1.json)
+    - [ ] **IMPL-003.1.1**: [Sub-subtask] → [📋](./.task/impl-003.1.1.json)
+
+## Status Legend
+- `▸` = Container task (has subtasks)
+- `- [ ]` = Pending leaf task  
+- `- [x]` = Completed leaf task
+- Indentation shows hierarchy (2 spaces per level)
 
 ## Notes
-[可选备注]
+[Optional notes]
 ```
 
 ## Agent Integration