feat(remote_wal): add skeleton for remote wal related to datanode

[niebayes]

I hereby agree to the terms of the GreptimeDB CLA

What's changed and what's your intention?

• Allocated wal options, including kafka topic, will be persisted in RegionInfo of DatanodeTableValue, and will be passed to datanodes through RegionCreateRequest. See: feat(remote_wal): add skeleton for remote wal related to meta srv #2933
• Upon initializing a region server, each region's wal options are decomposed from the RegionInfo in DatanodeTableValue. Those wal options are then merged into region options and passed to region workers.
• When a region worker receives a region create/open request, it extracts wal options from region options therein. The wal options are used to construct wal entry namespace when replaying memtable. On the other hand, the wal options are stored in MitoRegion to be used during writing to a region.
• When a region worker receives a RegionWriteRequest, it constructs wal entry namespaces with wal options. Entries are then written into the log store.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.

Refer to a related PR or issue link (optional)

[codecov]

Codecov Report

Attention: 91 lines in your changes are missing coverage. Please review.

Comparison is base (6ac47e9) 85.85% compared to head (c80369c) 85.70%.

Additional details and impacted files

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##           develop    #2941      +/-   ##
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- Coverage    85.85%   85.70%   -0.16%     
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  Files          770      775       +5     
  Lines       123951   124230     +279     
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+ Hits        106424   106471      +47     
- Misses       17527    17759     +232     

[killme2008]

LGTM

[v0y4g3r]

LGTM