fix bug: slider cannot drag to max value

[liuchao233]

修复 getClosestPoint 函数由于浮点数计算精度问题导致的 bug #27571

[vercel]

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[codecov]

Codecov Report

Merging #714 (e7f4155) into master (569fa38) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #714      +/-   ##
==========================================
+ Coverage   88.18%   88.20%   +0.01%     
==========================================
  Files          11       11              
  Lines         711      712       +1     
  Branches      180      183       +3     
==========================================
+ Hits          627      628       +1     
  Misses         84       84              

Impacted Files	Coverage Δ
src/utils.ts	94.11% <100.00%> (+0.07%)	⬆️

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