fix(types): defer unresolved forward refs in canonical subclasses

src/adcp/types/canonical_creative.py

@@ -690,6 +690,13 @@ def __pydantic_init_subclass__(cls, **kwargs: Any) -> None:
         Binding happens AFTER class creation, so pydantic never considers the
         name a field candidate; ``model_fields``, the JSON schema and the wire
         are all unaffected. Measured scope: one such validator, on one model.
+
+
+        The rebuild does not raise on an unresolved forward reference. A
+        subclass may annotate a field with a model defined later in its module
+        (``creatives: list["CreativeAsset"]``); plain pydantic defers such a
+        class until ``model_rebuild()``, and a raising rebuild here would turn
+        that ordinary pattern into an error at class creation.
         """
 
         removed = [name for name in cls.model_fields if is_legacy_creative_identity_key(name)]
@@ -698,7 +705,7 @@ def __pydantic_init_subclass__(cls, **kwargs: Any) -> None:
             cls.__annotations__.pop(name, None)
             setattr(cls, name, None)
         if removed:
-            cls.model_rebuild(force=True)
+            cls.model_rebuild(force=True, raise_errors=False)
 
     @model_validator(mode="before")
     @classmethod

tests/test_canonical_removed_fields.py

@@ -387,3 +387,25 @@ def on(line: int) -> list[str]:
             f"{checker} does not know {name} on the wire model {class_name} either, "
             f"so the refusal above proves nothing: {on(line)}"
         )
+
+
+def test_a_subclass_may_forward_reference_a_later_model() -> None:
+    """The removal's rebuild defers an unresolved forward reference, as pydantic does.
+
+    A subclass that re-inherits a removed field triggers the forced rebuild; if
+    that rebuild raises, annotating a field with a model defined further down the
+    module fails at class creation instead of at the caller's ``model_rebuild()``.
+    """
+    from adcp.types import PackageRequest
+
+    class WithForwardRef(PackageRequest):
+        later: list[Later] | None = None
+
+    class Later(BaseModel):
+        name: str
+
+    assert not WithForwardRef.__pydantic_complete__
+    WithForwardRef.model_rebuild()
+
+    assert "later" in WithForwardRef.model_fields
+    assert not set(_removed_names(WithForwardRef)) & set(WithForwardRef.model_fields)