Check committed file sizes

docs/internal/validation.md

@@ -37,6 +37,10 @@ with an inspection cause when their selected contents are unavailable. A
 replacement with no parsed version is reported with its go.mod path, line,
 directive, and target; versioned replacements are allowed. It runs after the
 workspace-file check using the same candidate inventory.
+The optional file-size check uses each blob's captured Git size, including
+symlink link-text bytes, and skips entries without a blob size such as gitlinks.
+It applies normalized literal file/directory exclusions with path-boundary
+matching, then returns the first oversized path with `FileSizeMeasurement`.
 `CandidateTree` gets metadata and bytes from Git objects, reads blob bytes
 lazily, and resolves destinations without consulting the worktree or
 neighboring files.