Deprecate snap server experimental option and add stable option

[pullurib]

PR description

Deprecate --Xsnapsync-server-enabled and add --snapsync-server-enabled instead.

Fixed Issue(s)

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[macfarla]

@garyschulte are we ready to remove the --X from snap server?

[garyschulte]

This isn't the flow we typically use when we promote something out of experimental. Typically we just alias the -X and after a quarter or so just remove the flag. We can add a deprecation message without adding an additional flag .

That said, this isn't a horrible pattern. At a minimum there needs to be a CHANGELOG.md entry for this PR, and some text in the upcoming deprecation body that references it.

[macfarla]

can you also update the log message in the startup summary to remove Experimental from:

# Experimental Snap Sync server enabled