Add support of the command DUMP

[AntiTopQuark]

Close #1946

Command Desc：

1. Adds support for the Dump command, which can be used as dump key.
2. Currently, the supported data types include: String, Hash, List, Set, ZSet. Redis also supports Stream and Module types; however, due to significant differences between kvrocks and Redis, Stream and Module types are not supported at this time.
3. Since kvrocks does not support encoding methods such as listpack and lzf, most types calculate the dump payload string using the RAW method.

Redis Documentation: https://redis.io/commands/dump/

[torwig]

@AntiTopQuark Running the ./x.py format should fix the linting issues.

[git-hulk]

Since kvrocks does not support encoding methods such as listpack and lzf, most types calculate the dump payload string using the RAW method.

I feel good about this, and we can make it work first and then improve.

[PragmaTwice]

If you want to assume it must be an RdbStringStream here, you can add a CHECK statement.

[PragmaTwice]

But TBH, to support output files rather than strings, we need a better solution here.

[git-hulk]

For the Redis dump command, it needs to echo the result to the client, so it should be good to keep in memory. Not sure if I misunderstood @PragmaTwice point.

[AntiTopQuark]

If you want to assume it must be an RdbStringStream here, you can add a CHECK statement.

I added a member attribute named type_ to RdbStream, and I ensure its safety by checking it before performing a static_cast

[AntiTopQuark]

But TBH, to support output files rather than strings, we need a better solution here.

Is it absolutely necessary to dump a value into a file?
If the goal is simply to dump the contents of specific keys, this can be readily achieved by redirecting the output of redis-cli to a designated file.
For dumping an entire RDB, might this feature be unnecessary? Directly utilizing kvrocks2redis would suffice. This requirement has been previously discussed: #1001 (comment)

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
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See analysis details on SonarCloud

[jihuayu]

The beautiful code that ignites a delightful start to my day.
Thank you!