Enhance skill generator documentation and templates

- Updated Phase 1 and Phase 2 documentation to include next phase links and data flow details.
- Expanded Phase 5 documentation to include comprehensive validation and README generation steps, along with validation report structure.
- Added purpose and usage context sections to various action and script templates (e.g., autonomous-action, llm-action, script-bash).
- Improved commands management by simplifying the command scanning logic and enabling/disabling commands through renaming files.
- Enhanced dashboard command manager to format group names and display nested groups with appropriate icons and colors.
- Updated LiteLLM executor to allow model overrides during execution.
- Added action reference guide and template reference sections to the skill-tuning SKILL.md for better navigation and understanding.

.claude/skills/skill-generator/templates/llm-action.md

@@ -2,6 +2,18 @@
 
 LLM 动作模板，用于在 Skill 中集成 LLM 调用能力。
 
+## Purpose
+
+为 Skill 生成 LLM 动作，通过 CCW CLI 统一接口调用 Gemini/Qwen/Codex 进行分析或生成。
+
+## Usage Context
+
+| Phase | Usage |
+|-------|-------|
+| Optional | 当 Skill 需要 LLM 能力时使用 |
+| Generation Trigger | 用户选择添加 llm 动作类型 |
+| Tools | gemini, qwen, codex (支持 fallback chain) |
+
 ---
 
 ## 配置结构