Drop deprecated_note hasattr pattern in HFCache

[electron-rare]

File: apps/api/src/kiki_cockpit/services/hf_cache.py:67-68

if hasattr(card, "deprecated_note"):
    card.deprecated_note = dep.note  # type: ignore[attr-defined]

card is typed as ModelCard but deprecated_note is only on ModelDetail. The HFCache only stores ModelCard objects, so deprecated_note will never be set. The type: ignore masks a real logic gap.

Fix: either add deprecated_note: str | None = None to ModelCard (so listings show the note), or drop the hasattr branch entirely (note only available via detail API).