refactor: refactor some metrics field name and display

[MrCroxx]

Refactor some metrics.

Ref: #66 .

[codecov]

Codecov Report

Merging #141 (5b5c0a7) into main (c197c3b) will decrease coverage by 0.09%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #141      +/-   ##
==========================================
- Coverage   82.59%   82.50%   -0.10%     
==========================================
  Files          78       78              
  Lines        7497     7469      -28     
==========================================
- Hits         6192     6162      -30     
- Misses       1305     1307       +2     

Impacted Files	Coverage Δ
wheel/src/service.rs	82.33% <100.00%> (-1.17%)	⬇️
wheel/src/worker/raft.rs	87.31% <100.00%> (-0.25%)	⬇️
storage/src/raft_log_store/block_cache.rs	84.00% <0.00%> (-4.00%)	⬇️
storage/src/raft_log_store/store.rs	89.27% <0.00%> (-0.77%)	⬇️
storage/src/raft_log_store/log.rs	89.95% <0.00%> (-0.48%)	⬇️
storage/src/utils/coding.rs	96.55% <0.00%> (+1.37%)	⬆️

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