Release validation source bytes after checks

docs/internal/validation.md

@@ -52,8 +52,11 @@ must close it when finished. The shared validation executor closes its tree on
 every return before product checks or build callbacks run. A metadata-only
 selection never starts the reader. Per-read contexts cancel an in-flight blob
 exchange without tying the reader lifetime to a short-lived caller context.
-Until formatting and parsed-result reuse are in place, regular-file bytes stay
-cached by object ID for the lifetime of the tree.
+Regular-file reads return independent caller-owned byte slices and are not
+retained by the tree. Symlink targets are retained as immutable owned strings
+by blob object ID; explicitly reading a symlink still returns independent
+bytes. The Go-format check caches only whether each successfully inspected
+object is formatted, then reports every unformatted path that refers to it.
 
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