Feature

Add simple search across repositories and persons (users). Available both via REST API and the server-rendered UI.

Scope

• Search targets: repositories (owner/name, description) and persons (username, display name).
• Match: simple case-insensitive substring match on the fields above. No ranking/full-text needed for v1.
• API: search endpoint returning both repo and person hits (e.g. GET /api/search?q=<term>), JSON payload with separate repositories and persons arrays. Respect visibility rules (only public repos + caller's own private repos).
• UI: search input (e.g. in the top nav) → results page grouping repo hits and person hits, each linking to the respective page.

Acceptance criteria

• Query matches repos by owner, name, description.
• Query matches persons by username and display name.
• API and UI return the same underlying results.
• Private repos not owned by the caller are excluded.
• Empty/blank query returns empty results (no error).

Notes

• Follow test-first: failing test before implementation.
• Update docs: docs/users/ (search UI/usage), docs/admins/ (new endpoint), and root README feature list.