perf(skill-loader): parallelize directory scanning

- Add async versions of skill discovery functions
- Create discoverAllSkillsAsync() with Promise.all parallelization
- Use fs.promises for async file operations
- Keep sync versions for backward compatibility

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/features/opencode-skill-loader/loader.ts

@@ -1,4 +1,5 @@
 import { existsSync, readdirSync, readFileSync } from "fs"
+import { promises as fs } from "fs"
 import { join, basename } from "path"
 import { homedir } from "os"
 import yaml from "js-yaml"
@@ -114,6 +115,62 @@ $ARGUMENTS
   }
 }
 
+async function loadSkillFromPathAsync(
+  skillPath: string,
+  resolvedPath: string,
+  defaultName: string,
+  scope: SkillScope
+): Promise<LoadedSkill | null> {
+  try {
+    const content = await fs.readFile(skillPath, "utf-8")
+    const { data, body } = parseFrontmatter<SkillMetadata>(content)
+    const frontmatterMcp = parseSkillMcpConfigFromFrontmatter(content)
+    const mcpJsonMcp = loadMcpJsonFromDir(resolvedPath)
+    const mcpConfig = mcpJsonMcp || frontmatterMcp
+
+    const skillName = data.name || defaultName
+    const originalDescription = data.description || ""
+    const isOpencodeSource = scope === "opencode" || scope === "opencode-project"
+    const formattedDescription = `(${scope} - Skill) ${originalDescription}`
+
+    const wrappedTemplate = `<skill-instruction>
+Base directory for this skill: ${resolvedPath}/
+File references (@path) in this skill are relative to this directory.
+
+${body.trim()}
+</skill-instruction>
+
+<user-request>
+$ARGUMENTS
+</user-request>`
+
+    const definition: CommandDefinition = {
+      name: skillName,
+      description: formattedDescription,
+      template: wrappedTemplate,
+      model: sanitizeModelField(data.model, isOpencodeSource ? "opencode" : "claude-code"),
+      agent: data.agent,
+      subtask: data.subtask,
+      argumentHint: data["argument-hint"],
+    }
+
+    return {
+      name: skillName,
+      path: skillPath,
+      resolvedPath,
+      definition,
+      scope,
+      license: data.license,
+      compatibility: data.compatibility,
+      metadata: data.metadata,
+      allowedTools: parseAllowedTools(data["allowed-tools"]),
+      mcpConfig,
+    }
+  } catch {
+    return null
+  }
+}
+
 /**
  * Load skills from a directory, supporting BOTH patterns:
  * - Directory with SKILL.md: skill-name/SKILL.md
@@ -164,6 +221,53 @@ function loadSkillsFromDir(skillsDir: string, scope: SkillScope): LoadedSkill[]
   return skills
 }
 
+/**
+ * Async version of loadSkillsFromDir using Promise-based fs operations.
+ */
+async function loadSkillsFromDirAsync(skillsDir: string, scope: SkillScope): Promise<LoadedSkill[]> {
+  const entries = await fs.readdir(skillsDir, { withFileTypes: true }).catch(() => [])
+  const skills: LoadedSkill[] = []
+
+  for (const entry of entries) {
+    if (entry.name.startsWith(".")) continue
+
+    const entryPath = join(skillsDir, entry.name)
+
+    if (entry.isDirectory() || entry.isSymbolicLink()) {
+      const resolvedPath = resolveSymlink(entryPath)
+      const dirName = entry.name
+
+      const skillMdPath = join(resolvedPath, "SKILL.md")
+      try {
+        await fs.access(skillMdPath)
+        const skill = await loadSkillFromPathAsync(skillMdPath, resolvedPath, dirName, scope)
+        if (skill) skills.push(skill)
+        continue
+      } catch {
+      }
+
+      const namedSkillMdPath = join(resolvedPath, `${dirName}.md`)
+      try {
+        await fs.access(namedSkillMdPath)
+        const skill = await loadSkillFromPathAsync(namedSkillMdPath, resolvedPath, dirName, scope)
+        if (skill) skills.push(skill)
+        continue
+      } catch {
+      }
+
+      continue
+    }
+
+    if (isMarkdownFile(entry)) {
+      const skillName = basename(entry.name, ".md")
+      const skill = await loadSkillFromPathAsync(entryPath, skillsDir, skillName, scope)
+      if (skill) skills.push(skill)
+    }
+  }
+
+  return skills
+}
+
 function skillsToRecord(skills: LoadedSkill[]): Record<string, CommandDefinition> {
   const result: Record<string, CommandDefinition> = {}
   for (const skill of skills) {
@@ -286,3 +390,41 @@ export function discoverOpencodeProjectSkills(): LoadedSkill[] {
   const opencodeProjectDir = join(process.cwd(), ".opencode", "skill")
   return loadSkillsFromDir(opencodeProjectDir, "opencode-project")
 }
+
+export async function discoverUserClaudeSkillsAsync(): Promise<LoadedSkill[]> {
+  const userSkillsDir = join(getClaudeConfigDir(), "skills")
+  return loadSkillsFromDirAsync(userSkillsDir, "user")
+}
+
+export async function discoverProjectClaudeSkillsAsync(): Promise<LoadedSkill[]> {
+  const projectSkillsDir = join(process.cwd(), ".claude", "skills")
+  return loadSkillsFromDirAsync(projectSkillsDir, "project")
+}
+
+export async function discoverOpencodeGlobalSkillsAsync(): Promise<LoadedSkill[]> {
+  const opencodeSkillsDir = join(homedir(), ".config", "opencode", "skill")
+  return loadSkillsFromDirAsync(opencodeSkillsDir, "opencode")
+}
+
+export async function discoverOpencodeProjectSkillsAsync(): Promise<LoadedSkill[]> {
+  const opencodeProjectDir = join(process.cwd(), ".opencode", "skill")
+  return loadSkillsFromDirAsync(opencodeProjectDir, "opencode-project")
+}
+
+export async function discoverAllSkillsAsync(options: DiscoverSkillsOptions = {}): Promise<LoadedSkill[]> {
+  const { includeClaudeCodePaths = true } = options
+
+  const opencodeProjectSkills = await discoverOpencodeProjectSkillsAsync()
+  const opencodeGlobalSkills = await discoverOpencodeGlobalSkillsAsync()
+
+  if (!includeClaudeCodePaths) {
+    return [...opencodeProjectSkills, ...opencodeGlobalSkills]
+  }
+
+  const [projectSkills, userSkills] = await Promise.all([
+    discoverProjectClaudeSkillsAsync(),
+    discoverUserClaudeSkillsAsync(),
+  ])
+
+  return [...opencodeProjectSkills, ...projectSkills, ...opencodeGlobalSkills, ...userSkills]
+}