fix(cli): reject non-object project config roots

[user-github-me]

A hyperframes.json containing an array, string, number or boolean is currently reported as a valid default config. Rendering consequently reports zero catalog items instead of the existing unreadable-manifest signal.

Require an object root before normalizing the parsed JSON, using the existing object guard. Partial object configs retain their defaults, unreadable configs retain the existing command fallback, and the file is never rewritten.

Validation:

• Seven fail-first cases prove incorrect read status and catalog reporting; null, corrupt, missing and partial-object controls retain their behavior.
• All 260 related config, schema, catalog, add, render-plan and telemetry tests pass.
• The built config reader correctly handles ten real on-disk fixtures and preserves their bytes.
• CLI build/typecheck, repository lint, formatting, commit hooks and comment checks pass.