[Mzack9999]

Closes #213

Proposed changes

• The logging layer keeps at most -max-dump-body-size of the request body (1 MB when the flag is not set). The limit no longer depends on Content-Length, so chunked bodies are bounded too.
• The bytes read for the log are put back in front of the body, so handlers still read the full request.
• The body is read only when a log output needs it (verbose or JSON log).

Proof

New tests TestLogLayerBoundsChunkedBody and TestLogLayerSkipsBodyWithoutLog. Existing tests pass.