Explain the point to whoever opens the admin

The overview leads with what Logbuch is for, a new Anleitung page renders
the editorial guide for humans, and the user list stops claiming accounts
come from a shell command: they appear on first sign in.

next.config.ts

@@ -14,6 +14,7 @@ const config: NextConfig = {
 		'/api/v1/skill': ['./docs/skill.md'],
 		'/admin/api/files/skill': ['./docs/skill.md'],
 		'/admin/api/files/style-guide': ['./docs/style-guide.md'],
+		'/admin/guide': ['./docs/style-guide.md'],
 		'/': ['./node_modules/drizzle-orm/**'],
 		'/api/v1/media': sharpNative,
 		'/admin/media': sharpNative,