fix: leave out core files the core refuses by size

A core extra resolved by name shipped on existence platforms even when
the core's own size check turns the copy away. The RetroPie pack carried
the 128 KB Apple IIGS ROM as Basilisk II's ROM (min 512 KB). The builder,
the manifest and verify now read validation.core_size_refusal, which
accepts a copy any version of the same profile slot takes.

scripts/packextras.py

@@ -176,7 +176,10 @@ class ExtraResolver:
         validation_index: dict,
         validation_owners: dict | None,
         offline: bool | None = True,
+        *,
+        profiles: dict,
     ) -> None:
+        self.profiles = profiles
         self.db = db
         self.bios_dir = bios_dir
         self.zip_contents = zip_contents
@@ -188,7 +191,7 @@ class ExtraResolver:
     def resolve(self, fe: dict, dest: str) -> tuple[str | None, str, str]:
         """(local copy or None, resolver status, the core's disagreement)."""
         from packresolve import resolve_file
-        from validation import validated_choice
+        from validation import core_size_refusal, extra_alternatives, validated_choice
 
         local_path, status = resolve_file(
             fe, self.db, self.bios_dir, self.zip_contents,
@@ -201,6 +204,12 @@ class ExtraResolver:
             fe, local_path, self.db, self.validation_index, self.bios_dir, None,
             dest, self.validation_owners,
         )
+        # The platform never reads the bytes, the core does: a copy it turns
+        # away by its own size check is not its file, on any platform.
+        if core_size_refusal(
+            fe, local_path, extra_alternatives(fe, self.profiles)
+        ):
+            return None, "not_found", ""
         return local_path, status, disagreement