chore: remove old metrics, reclaim drop indices first

[MrCroxx]

Signed-off-by: MrCroxx mrcroxx@outlook.com

[codecov-commenter]

Codecov Report

Merging #60 (5127d59) into main (809ca83) will decrease coverage by 0.50%.
The diff coverage is 8.33%.

@@            Coverage Diff             @@
##             main      #60      +/-   ##
==========================================
- Coverage   67.93%   67.43%   -0.50%     
==========================================
  Files          31       30       -1     
  Lines        3614     3621       +7     
==========================================
- Hits         2455     2442      -13     
- Misses       1159     1179      +20     

Impacted Files	Coverage Δ
foyer-common/src/code.rs	60.00% <0.00%> (ø)
foyer-intrusive/src/core/adapter.rs	97.87% <ø> (ø)
foyer-storage-bench/src/main.rs	0.00% <0.00%> (ø)
foyer-storage/src/admission/mod.rs	0.00% <0.00%> (ø)
foyer-storage/src/admission/rated_random.rs	0.00% <0.00%> (ø)
foyer/src/lib.rs	0.00% <ø> (ø)
foyer-storage/src/store.rs	88.93% <75.00%> (-0.79%)	⬇️
foyer-storage/src/reclaimer.rs	84.61% <100.00%> (-0.39%)	⬇️