HACS dashboard doesn't show local brand icons (HA 2026.3+)

Description

Starting with Home Assistant 2026.3, custom integrations can ship their own brand images in a rand/ directory inside the integration folder. The home-assistant/brands repository no longer accepts PRs for custom integrations (see announcement).

HA serves these icons via the local API at /api/brands/integration/{domain}/icon.png, and they display correctly on the Integrations page, device pages, and everywhere else in the HA frontend.

However, the HACS dashboard still fetches icons from data-v2.hacs.xyz, which doesn't have icons for custom integrations that only provide local brand assets. This results in a missing/blank icon in the HACS store listing.

Steps to reproduce

1. Create a custom integration with a \rand/\ folder containing \icon.png\ (following the HA docs)
2. Add the repo as a custom repository in HACS
3. The icon appears blank/missing in the HACS dashboard
4. The same icon works correctly on the HA Integrations page (/api/brands/integration/{domain}/icon.png\ returns 200)

Expected behavior

HACS should fall back to the local HA brands API (/api/brands/integration/{domain}/icon.png) when the icon is not available on \data-v2.hacs.xyz.

Environment

• HA version: 2026.3.2
• HACS version: 2.0.5
• Integration: ha-hi3510 (has \rand/\ folder with icon.png and logo.png)