feat(server): add recipe-based model management (#2176)

AGENTS.md

@@ -83,6 +83,8 @@ documentation.
   and debugging.
 * `examples/common/` - shared example support code.
 * `examples/server/` - server application built on top of the library.
+  Before modifying built-in recipes, read and follow
+  [the built-in recipe policy](examples/server/recipes/README.md).
 * `examples/server/frontend/` - git submodule containing independent frontend
   code. Avoid modifying it unless explicitly requested.