docs: update documentation to OKF v0.1 format

docs/index.md

@@ -43,8 +43,9 @@ they need. Last regenerated 2026-07-22T10:32:00Z.
   `/change-password`, and first-admin registration.
 * [Setup Endpoint](/api/setup.md) - Dedicated `POST /api/v1/setup/create-admin`
   used only while no administrator exists.
-* [Admin Endpoints](/api/admin.md) - User management endpoints
-  (admin role required).
+* [Admin Endpoints](/api/admin.md) - Admin-only endpoints covering user
+  management, general settings (`/api/v1/admin/general/*`), and
+  categories (`/api/v1/admin/categories/*`).
 * [System Endpoints](/api/system.md) - Bootstrap, event status, public SSE
   streams, public event-window settings, and the authenticated
   `/events/status` SSE stream.
@@ -57,8 +58,16 @@ they need. Last regenerated 2026-07-22T10:32:00Z.
 * [Setup Form Field Errors](/guides/setup-field-errors.md) - Pure
   helpers that translate reactive-form state into the inline validation
   messages on the first-admin modal.
-* [Admin Shell & User Management](/guides/admin-shell.md) - How admins
-  navigate the post-login shell and reach the user-management area.
+* [Admin Shell & Side Navigation](/guides/admin-shell.md) - How admins
+  navigate the post-login admin area side-nav (General, Challenges,
+  Players, Blog, System) and reach the enabled child pages.
+* [Admin — General Settings](/guides/admin-general-settings.md) - How an
+  admin edits platform-wide settings (page title, logo, theme, event
+  window, default challenge IP, registrations, welcome Markdown) at
+  `/admin/general`.
+* [Admin — Categories](/guides/admin-categories.md) - How an admin lists,
+  creates, edits, and deletes challenge categories at `/admin/categories`,
+  including system-row and challenge-attached protection.
 * [Authenticated Shell](/guides/authenticated-shell.md) - The header, LED
   + countdown, quick-jump tabs, user menu, and SSE lifecycle that frame
   every signed-in page.