docs: generate code from externally published schemas

AGENTS.md

@@ -13,14 +13,17 @@
 - Never commit autogenerated code to the repository. This applies to backend,
   frontend, shared packages, and every other module, including generated
   protobuf bindings, API clients, serializers, and framework-generated code.
-- Commit the schema source definitions, generator configuration, and reproducible
-  generation commands instead. Generate code from the schema source at build
-  time, before any dependent validation or compilation steps, including in CI.
+- Use externally published schemas as generation inputs. Do not embed or commit
+  schema snapshots in the repository. Commit external schema references,
+  generator configuration, and reproducible generation commands instead.
+- Fetch the externally published schemas and generate code at build time, before
+  any dependent validation or compilation steps, including in CI.
 - Keep generated outputs ignored by Git. Do not force-add ignored generated
   files or copy generated code into tracked source files.
-- Change the source definitions or generator inputs rather than editing
-  generated outputs. Document the generation workflow so a clean checkout can
-  build without committed generated code.
+- Change schema sources in their owning project or update external schema
+  references and generator inputs rather than editing generated outputs.
+  Document the generation workflow so a clean checkout can build without
+  committed generated code or embedded schema snapshots.
 
 ## Local development tooling