fix: Skills API 增加项目级 .claude/skills 扫描

列表接口 (route.ts):
- 新增 getProjectSkillsDir + scanProjectSkills 扫描 .claude/skills/*/SKILL.md
- 解析 YAML front matter 取 name/description，source 为 "project"
- 与 project commands 去重（commands 优先）

按名查找接口 ([name]/route.ts):
- findSkillFile 查找链路扩展：project commands → project skills → global → installed
- 支持目录名直接匹配和 front matter name 匹配
- GET 对 SKILL.md 从 front matter 取 description
- PUT 增加 cwd 参数支持

修复与 Agent SDK 的目录约定不一致问题：SDK 会加载项目级
.claude/skills，但本项目 API 之前只扫 commands 目录和用户级 skills。

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/api/skills/[name]/route.ts

@@ -12,6 +12,10 @@ function getProjectCommandsDir(cwd?: string): string {
   return path.join(cwd || process.cwd(), ".claude", "commands");
 }
 
+function getProjectSkillsDir(cwd?: string): string {
+  return path.join(cwd || process.cwd(), ".claude", "skills");
+}
+
 function getInstalledSkillsDir(): string {
   return path.join(os.homedir(), ".agents", "skills");
 }
@@ -157,11 +161,39 @@ function findSkillFile(
   const installedSource = options?.installedSource;
 
   if (!options?.installedOnly) {
-    // Check project first, then global, then installed (~/.agents/skills/ and ~/.claude/skills/)
+    // Check project commands → project skills → global commands → installed
     const projectPath = path.join(getProjectCommandsDir(options?.cwd), `${name}.md`);
     if (fs.existsSync(projectPath)) {
       return { filePath: projectPath, source: "project" };
     }
+
+    // Check project-level .claude/skills/{name}/SKILL.md
+    const projectSkillPath = path.join(getProjectSkillsDir(options?.cwd), name, "SKILL.md");
+    if (fs.existsSync(projectSkillPath)) {
+      return { filePath: projectSkillPath, source: "project" };
+    }
+
+    // Check project-level skills by front matter name (scan all subdirs)
+    const projectSkillsDir = getProjectSkillsDir(options?.cwd);
+    if (fs.existsSync(projectSkillsDir)) {
+      try {
+        const entries = fs.readdirSync(projectSkillsDir, { withFileTypes: true });
+        for (const entry of entries) {
+          if (!entry.isDirectory() || entry.name.startsWith(".")) continue;
+          if (entry.name === name) continue; // already checked above
+          const skillMdPath = path.join(projectSkillsDir, entry.name, "SKILL.md");
+          if (!fs.existsSync(skillMdPath)) continue;
+          const skillContent = fs.readFileSync(skillMdPath, "utf-8");
+          const meta = parseSkillFrontMatter(skillContent);
+          if (meta.name === name) {
+            return { filePath: skillMdPath, source: "project" };
+          }
+        }
+      } catch {
+        // ignore read errors
+      }
+    }
+
     const globalPath = path.join(getGlobalCommandsDir(), `${name}.md`);
     if (fs.existsSync(globalPath)) {
       return { filePath: globalPath, source: "global" };
@@ -238,9 +270,16 @@ export async function GET(
 
     const content = fs.readFileSync(found.filePath, "utf-8");
     const firstLine = content.split("\n")[0]?.trim() || "";
-    const description = firstLine.startsWith("#")
-      ? firstLine.replace(/^#+\s*/, "")
-      : firstLine || `Skill: /${name}`;
+    let description: string;
+
+    if (found.filePath.endsWith("SKILL.md")) {
+      const meta = parseSkillFrontMatter(content);
+      description = meta.description || (firstLine.startsWith("#") ? firstLine.replace(/^#+\s*/, "") : firstLine || `Skill: /${name}`);
+    } else {
+      description = firstLine.startsWith("#")
+        ? firstLine.replace(/^#+\s*/, "")
+        : firstLine || `Skill: /${name}`;
+    }
 
     return NextResponse.json({
       skill: {
@@ -271,6 +310,7 @@ export async function PUT(
 
     const url = new URL(request.url);
     const sourceParam = url.searchParams.get("source");
+    const cwdParam = url.searchParams.get("cwd") || undefined;
     const installedSource =
       sourceParam === "agents" || sourceParam === "claude"
         ? (sourceParam as InstalledSource)
@@ -283,8 +323,8 @@ export async function PUT(
     }
 
     const found = installedSource
-      ? findSkillFile(name, { installedSource, installedOnly: true })
-      : findSkillFile(name);
+      ? findSkillFile(name, { installedSource, installedOnly: true, cwd: cwdParam })
+      : findSkillFile(name, { cwd: cwdParam });
     if (found && "conflict" in found) {
       return NextResponse.json(
         { error: "Multiple skills with different content", sources: found.sources },

src/app/api/skills/route.ts

@@ -24,6 +24,10 @@ function getProjectCommandsDir(cwd?: string): string {
   return path.join(cwd || process.cwd(), ".claude", "commands");
 }
 
+function getProjectSkillsDir(cwd?: string): string {
+  return path.join(cwd || process.cwd(), ".claude", "skills");
+}
+
 function getPluginCommandsDirs(): string[] {
   const dirs: string[] = [];
   const marketplacesDir = path.join(os.homedir(), ".claude", "plugins", "marketplaces");
@@ -57,6 +61,40 @@ function getClaudeSkillsDir(): string {
   return path.join(os.homedir(), ".claude", "skills");
 }
 
+/**
+ * Scan project-level skills from .claude/skills/{name}/SKILL.md.
+ * Each subdirectory may contain a SKILL.md with optional YAML front matter.
+ */
+function scanProjectSkills(dir: string): SkillFile[] {
+  const skills: SkillFile[] = [];
+  if (!fs.existsSync(dir)) return skills;
+
+  try {
+    const entries = fs.readdirSync(dir, { withFileTypes: true });
+    for (const entry of entries) {
+      if (!entry.isDirectory() || entry.name.startsWith(".")) continue;
+      const skillMdPath = path.join(dir, entry.name, "SKILL.md");
+      if (!fs.existsSync(skillMdPath)) continue;
+
+      const content = fs.readFileSync(skillMdPath, "utf-8");
+      const meta = parseSkillFrontMatter(content);
+      const name = meta.name || entry.name;
+      const description = meta.description || `Skill: /${name}`;
+
+      skills.push({
+        name,
+        description,
+        content,
+        source: "project",
+        filePath: skillMdPath,
+      });
+    }
+  } catch {
+    // ignore read errors
+  }
+  return skills;
+}
+
 function computeContentHash(content: string): string {
   return crypto.createHash("sha1").update(content, "utf8").digest("hex");
 }
@@ -240,6 +278,18 @@ export async function GET(request: NextRequest) {
     const globalSkills = scanDirectory(globalDir, "global");
     const projectSkills = scanDirectory(projectDir, "project");
 
+    // Scan project-level skills (.claude/skills/*/SKILL.md)
+    const projectSkillsDir = getProjectSkillsDir(cwd);
+    console.log(`[skills] Scanning project skills: ${projectSkillsDir} (exists: ${fs.existsSync(projectSkillsDir)})`);
+    const projectLevelSkills = scanProjectSkills(projectSkillsDir);
+    console.log(`[skills] Found ${projectLevelSkills.length} project-level skills`);
+
+    // Deduplicate: project commands take priority over project skills with the same name
+    const projectCommandNames = new Set(projectSkills.map((s) => s.name));
+    const dedupedProjectSkills = projectLevelSkills.filter(
+      (s) => !projectCommandNames.has(s.name)
+    );
+
     const agentsSkillsDir = getInstalledSkillsDir();
     const claudeSkillsDir = getClaudeSkillsDir();
     console.log(`[skills] Scanning installed: ${agentsSkillsDir} (exists: ${fs.existsSync(agentsSkillsDir)})`);
@@ -267,8 +317,8 @@ export async function GET(request: NextRequest) {
       pluginSkills.push(...scanDirectory(dir, "plugin"));
     }
 
-    const all = [...globalSkills, ...projectSkills, ...installedSkills, ...pluginSkills];
-    console.log(`[skills] Found: global=${globalSkills.length}, project=${projectSkills.length}, installed=${installedSkills.length}, plugin=${pluginSkills.length}`);
+    const all = [...globalSkills, ...projectSkills, ...dedupedProjectSkills, ...installedSkills, ...pluginSkills];
+    console.log(`[skills] Found: global=${globalSkills.length}, project=${projectSkills.length}, projectSkills=${dedupedProjectSkills.length}, installed=${installedSkills.length}, plugin=${pluginSkills.length}`);
 
     return NextResponse.json({ skills: all });
   } catch (error) {