feat(shared): add opencode-command-dirs utility for multi-level command discovery

src/shared/opencode-command-dirs.ts

@@ -0,0 +1,24 @@
+import { basename, dirname, join } from "node:path"
+import { getOpenCodeConfigDir } from "./opencode-config-dir"
+import type { OpenCodeConfigDirOptions } from "./opencode-config-dir-types"
+
+function getParentOpencodeConfigDir(configDir: string): string | null {
+  const parentDir = dirname(configDir)
+  if (basename(parentDir) !== "profiles") {
+    return null
+  }
+
+  return dirname(parentDir)
+}
+
+export function getOpenCodeCommandDirs(options: OpenCodeConfigDirOptions): string[] {
+  const configDir = getOpenCodeConfigDir(options)
+  const parentConfigDir = getParentOpencodeConfigDir(configDir)
+
+  return Array.from(
+    new Set([
+      join(configDir, "command"),
+      ...(parentConfigDir ? [join(parentConfigDir, "command")] : []),
+    ])
+  )
+}