Project NOMAD's bundled docs (`/app/docs/*.md` and `README.md`) each
embed as their own KB source — currently rendering as 12+ individual
rows that swamp user-uploaded content in the Stored Files table.
Collapse them into one informational row:
> Project NOMAD documentation · 12 files · Managed by NOMAD
The admin-docs row hides the Delete button (those files would be
re-embedded on the next sync anyway, so deleting is a footgun). User
uploads and ZIMs keep their existing per-row Delete UX.
Also adds deterministic sort: ZIMs → user uploads → admin docs → other,
alphabetical within each bucket. Pure frontend change — `/api/rag/files`
response shape unchanged.
Decision logic extracted to `kb_file_grouping.ts` with 9 unit tests
covering bucket classification, sort order, count noun pluralization,
and empty-input handling.
c64ec97de4