feat: introduce the region lease keeper

[WenyXu]

I hereby agree to the terms of the GreptimeDB CLA

What's changed and what's your intention?

Introduces the new region lease keeper, which utilizes the LeaderCachedKvStore.

The find_staled_leader_regions method, returns staled Leader regions:

• It returns a region if the datanode_id isn't the corresponding leader peer in region_routes.
  • Expected as RegionRole::Follower regions.
  • Unexpected RegionRole::Leader regions.
• It returns a region if the region's table metadata is not found.

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)

#2636

[codecov]

Codecov Report

Merging #2645 (32ec24d) into develop (479ffe5) will decrease coverage by 0.38%.
The diff coverage is 92.89%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2645      +/-   ##
===========================================
- Coverage    85.10%   84.73%   -0.38%     
===========================================
  Files          754      758       +4     
  Lines       120911   121219     +308     
===========================================
- Hits        102902   102710     -192     
- Misses       18009    18509     +500     

[WenyXu]

@MichaelScofield @fengjiachun PTAL

[fengjiachun]

LGTM

[WenyXu]

@MichaelScofield PTAL