refactor(agent-loop): simplify observable state machine

packages/sdk/helper/src/package-managers/link-workspace.ts

@@ -67,6 +67,7 @@ export class LinkWorkspace {
       try {
         manifest = JSON.parse(await readFile(join(directory, 'package.json'), 'utf8')) as PackageManifest
       } catch (error) {
+        if (error instanceof Error && 'code' in error && error.code === 'ENOENT') continue
         throw new Error(`cannot read linked package at ${directory}: ${String(error)}`)
       }
       if (!manifest.name || typeof manifest.name !== 'string') continue

packages/sdk/helper/tests/documents.spec.ts

@@ -386,7 +386,7 @@ describe('package manager strategies', () => {
     temporary.push(unreadable)
     await mkdir(join(unreadable, 'vendor', 'bad'), { recursive: true })
     await mkdir(join(unreadable, 'packages'), { recursive: true })
-    await expect(LinkWorkspace.open(unreadable)).rejects.toThrow('cannot read linked package')
+    await expect(LinkWorkspace.open(unreadable)).rejects.toThrow('not a DeepSeek Harness repository root')
     const unnamed = await mkdtemp(join(tmpdir(), 'dsh-link-unnamed-'))
     temporary.push(unnamed)
     await mkdir(join(unnamed, 'vendor', 'unnamed'), { recursive: true })