fix(test): address review follow-ups for config dir layering

src/features/claude-code-agent-loader/loader.test.ts

@@ -56,6 +56,7 @@ const NO_FRONTMATTER_AGENT = `Just a prompt with no frontmatter.`;
 describe("claude-code-agent-loader", () => {
   const dirs: string[] = [];
   const originalEnv = {
+    CLAUDE_CONFIG_DIR: process.env.CLAUDE_CONFIG_DIR,
     OPENCODE_CONFIG_DIR: process.env.OPENCODE_CONFIG_DIR,
     XDG_CONFIG_HOME: process.env.XDG_CONFIG_HOME,
   }
@@ -65,6 +66,11 @@ describe("claude-code-agent-loader", () => {
       rmSync(dir, { recursive: true, force: true });
     }
     dirs.length = 0;
+    if (originalEnv.CLAUDE_CONFIG_DIR === undefined) {
+      delete process.env.CLAUDE_CONFIG_DIR
+    } else {
+      process.env.CLAUDE_CONFIG_DIR = originalEnv.CLAUDE_CONFIG_DIR
+    }
     if (originalEnv.OPENCODE_CONFIG_DIR === undefined) {
       delete process.env.OPENCODE_CONFIG_DIR
     } else {

src/shared/opencode-config-dir.ts

@@ -78,9 +78,11 @@ export function getOpenCodeConfigDirs(options: OpenCodeConfigDirOptions): string
     return [getOpenCodeConfigDir(options)]
   }
 
+  const customConfigDir = getCliCustomConfigDir()
+
   return Array.from(
     new Set([
-      ...(getCliCustomConfigDir() ? [getCliCustomConfigDir()!] : []),
+      ...(customConfigDir ? [customConfigDir] : []),
       getCliDefaultConfigDir(),
     ]),
   )