feat: 更新技能管理工具文档，明确技能创建和修改的正确流程及存储路径

src/gateway/default_agent_prompt.md

@@ -71,7 +71,21 @@
 - 如果任务涉及文件、命令、配置或下一步操作，优先给出最关键的那部分。
 
 ## PICO配置
-- Skill安装在[basedir]/skills
+
+### 技能系统
+
+- **技能存储路径**:
+  - 项目级: `{project-root}/.picobot/skills/{skill-name}/SKILL.md`
+  - 用户级: `~/.picobot/skills/{skill-name}/SKILL.md`
+
+- **创建/修改技能**:
+  - 必须使用 `skill_manage` 工具的 `create` 或 `update` action
+  - 不要使用 `write` 工具直接写入技能文件
+  - `skill_manage` 会自动创建正确的目录结构
+
+- **使用技能**:
+  - Skill 不是工具名，不能直接调用
+  - 必须先调用 `skill_activate` 工具激活技能，再按指令执行
 
 ## 补充要求
 

src/tools/skill_manage.rs

@@ -24,15 +24,18 @@ impl Tool for SkillManageTool {
 
     fn description(&self) -> &str {
         "Manage PicoBot skills. Actions: list, get, create, update, delete, disable, reload.\n\n\
+        IMPORTANT: To create or modify skills, ALWAYS use this tool (skill_manage), NOT the write tool.\n\n\
         Skill Structure:\n\
         - Folder name: kebab-case (lowercase with hyphens, e.g., 'my-cool-skill')\n\
         - Required: SKILL.md with YAML frontmatter + Markdown body\n\
         - Optional folders: scripts/, references/, assets/\n\
-        - Storage: .picobot/skills/{name}/SKILL.md or ~/.picobot/skills/{name}/SKILL.md\n\n\
+        - Storage paths (created automatically by this tool):\n\
+          - Project scope: {current-dir}/.picobot/skills/{name}/SKILL.md\n\
+          - User scope: ~/.picobot/skills/{name}/SKILL.md\n\n\
         Installing from Zip:\n\
-        - Extract skill folders to skills/ directory\n\
+        - Extract skill folders to .picobot/skills/ directory (NOT skills/)\n\
         - If zip contains multiple skills, extract each subfolder separately\n\
-        - Final structure: skills/{skill-name}/SKILL.md"
+        - Final structure: .picobot/skills/{skill-name}/SKILL.md"
     }
 
     fn parameters_schema(&self) -> serde_json::Value {
@@ -51,7 +54,7 @@ impl Tool for SkillManageTool {
                 },
                 "name": {
                     "type": "string",
-                    "description": "Skill folder name in kebab-case (e.g., 'my-cool-skill', 'code-review'). Must match the folder name under .picobot/skills/ or ~/.picobot/skills/"
+                    "description": "Skill folder name in kebab-case (e.g., 'my-cool-skill', 'code-review'). The skill_manage tool automatically creates files at .picobot/skills/{name}/SKILL.md (project scope) or ~/.picobot/skills/{name}/SKILL.md (user scope)."
                 },
                 "names": {
                     "type": "array",