[anqorithm]

BodyDump omits successfully written response bytes when the underlying writer returns a partial count and an error. The bounded writer returns before recording the prefix, and the unlimited io.MultiWriter path stops before copying it to the dump buffer.

Use the existing dump writer for both modes and record only the accepted prefix before returning the write error. Preserve the dump limit and report io.ErrShortWrite for a short write with no error. Six regression cases cover bounded/unlimited dumps and explicit/silent write failures; the original partial-error cases fail before the fix. Full race tests, build, go vet, staticcheck, golint and diff checks pass.