Check committed file sizes

docs/consumers/check.md

@@ -54,6 +54,14 @@ path, line, and target as `local-replacements`; versioned replacements are
 permitted. Committed module symlinks are resolved within the candidate. Parse
 and inspection errors retain their causes, and the rule applies even when
 `GOWORK=off`. Its zero value disables the check.
+Set `Validation.FileSize` to check each committed blob against a byte limit.
+Nil disables the check; an empty object enables the default of 1,000,000
+decimal bytes. `LimitBytes` is strict greater-than, accepts zero, and rejects
+negative values. `Exclusions` contains literal repository-relative files or
+directories; excluded directories include descendants. Symlink blobs are
+measured by link-text bytes, and gitlinks are omitted. The check applies to the
+captured candidate and reports one oversized file with its measurement as
+`file-size`; it does not measure historical or aggregate size.
 ReleaseKit calls `AdditionalChecks` once after shared validation when supplied.
 It does not download a different toolchain automatically. If race prerequisites
 are unavailable, the `go-test` check fails rather than being skipped; a selected