feat: skills import — 从其他工具复制 Skills 的交互式 TUI

新增:
- skills_importer.rs: 扫描已知路径 (Claude Code, Agent Skills,
  OpenCode, pi) 发现可导入的 Skill
- ias skills list: 列出可导入的 Skill
- ias skills import: 交互式多选 TUI (dialoguer MultiSelect)
  复制选中的 Skill 到 skills/ 目录

依赖: dialoguer + console + dirs

src/main.rs

@@ -5,12 +5,13 @@ mod db;
 mod llm;
 mod logger;
 mod scheduler;
+mod skills_importer;
 mod state;
 mod tools;
 mod wechat;
 
 use clap::Parser;
-use cli::{Cli, Commands};
+use cli::{Cli, Commands, SkillsAction};
 use config::AppConfig;
 use context::MemoryStore;
 use db::Database;
@@ -90,6 +91,9 @@ async fn main() {
         Commands::Service => {
             cmd_listen(true, false, &database, &file_state, &config, &memory_store).await
         }
+        Commands::Skills { action } => {
+            cmd_skills(action).await;
+        }
     }
 }
 
@@ -749,3 +753,66 @@ async fn cmd_send(
         Err(e) => error!("发送失败: {}", e),
     }
 }
+
+async fn cmd_skills(action: SkillsAction) {
+    use dialoguer::{MultiSelect, theme::ColorfulTheme};
+    use console::Term;
+
+    match action {
+        SkillsAction::List => {
+            let discovered = skills_importer::discover_skills();
+            if discovered.is_empty() {
+                println!("未发现可导入的 Skill");
+                return;
+            }
+            println!("发现 {} 个可导入的 Skill:", discovered.len());
+            for (source, name, _path) in &discovered {
+                println!("  [{source}] {name}");
+            }
+        }
+        SkillsAction::Import => {
+            let discovered = skills_importer::discover_skills();
+            if discovered.is_empty() {
+                println!("未发现可导入的 Skill");
+                return;
+            }
+
+            let items: Vec<String> = discovered.iter()
+                .map(|(src, name, _)| format!("[{}] {}", src, name))
+                .collect();
+
+            println!("发现 {} 个可导入的 Skill（空格选择，回车确认，q 退出）:", discovered.len());
+            let selection = MultiSelect::with_theme(&ColorfulTheme::default())
+                .items(&items)
+                .interact_on(&Term::stderr())
+                .unwrap_or_default();
+
+            if selection.is_empty() {
+                println!("未选择任何 Skill");
+                return;
+            }
+
+            let dest = std::path::PathBuf::from("skills");
+            std::fs::create_dir_all(&dest).ok();
+
+            let mut imported = 0;
+            let mut skipped = 0;
+            for idx in selection {
+                let (src, name, path) = &discovered[idx];
+                println!("  导入 [{src}] {name}...");
+                match skills_importer::copy_skill(path, name, &dest) {
+                    Ok(_) => {
+                        println!("    ✅ 已导入");
+                        imported += 1;
+                    }
+                    Err(e) => {
+                        println!("    ⚠️ {e}");
+                        skipped += 1;
+                    }
+                }
+            }
+            println!("\n完成：导入 {imported} 个，跳过 {skipped} 个");
+            println!("重启 iAs 后生效");
+        }
+    }
+}