Simple support for DUMP and RESTORE

[alyssaruth]

Closes #401

Simple implementation for DUMP and RESTORE which just supports string keys:

• Attempting to dump a different key type will produce WRONGTYPE Operation against a key holding the wrong kind of value
• For RESTORE I've implemented the REPLACE and ABSTTL optional flags, but not IDLETIME or FREQ (wasn't immediately obvious to me what these were 🤷‍♀️ )

I have also:

• Renamed the existing Dump to DebugDump to avoid confusion
• Extracted constants for the various key types
• Collected common validation into validCMD and plugged it in for all the existing generic commands. Happy to do this for the remainder as well if the approach looks good to you 😄

[alicebob]

On Sat, May 17, 2025 at 03:53:02PM -0700, Alyssa wrote: Closes #401 Simple implementation for `DUMP` and `RESTORE` which just supports string keys:

Thanks! I'll have a look soon.