Add Controls to Constrain Window Size to Protocol Limits

[felixhandte]

This PR adds convenience options that ensure Zstd produces compressed outputs compatible with protocols that place limits on the window size. Currently, it supports two protocols:

• The zstd HTTP Content-Encoding (RFC 8878 and RFC 9659).
• The dcz HTTP Content-Encoding (draft-ietf-httpbis-compression-dictionary-19).

This option is exposed as a new CCtx param ZSTD_c_constrainWindowForProtocol and a corresponding CLI argument --constrain-window.

To-Do:

• [x] Add CCtx Param.
• [x] Add CLI Flags.
• [x] Add tests.

[felixhandte]

cc @pmeenan, @nidhijaju. We'd talked about this being desirable for adoption of dcz. Take a look and make sure it meets your needs? It should go out in the next Zstd release which is coming very soon.