fix(core): use official Vite+ brand icon and load embedded client via runtime injection

- branding: use the official Vite+ brand assets (icon + wordmark, light/dark)
  from voidzero-dev/community-design-resources for the hub-ui logo/wordmark/
  favicon, replacing the hand-drawn placeholder mark.
- injection: load `<base>embedded.js` via an inline module that creates the
  script element at runtime instead of a static `<script type=module src>`.
  A static root-relative module src makes Vite pre-transform the hub-served
  bootstrap through its own pipeline (logging "Failed to load url
  /__devtools/embedded.js"); depending on the Vite version it can shadow the
  real module, breaking the client's `import.meta.url`-relative branding.json
  fetch so the dock falls back to devframe's default accent instead of the
  Vite DevTools primary color. Runtime injection keeps embedded.js out of
  Vite's module graph, so branding resolves correctly.

The hub-ui branding mechanism itself is correct (primaryColor feeds
`--devframe-primary` and the derived ramp), so no upstream change is needed.

Author: antfubot