feat(checkbox): allow indeterminate as the value

[brc-dd]

closes #335

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[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.01% 🎉

Comparison is base (4276ebb) 84.59% compared to head (0aa0e76) 84.60%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #336      +/-   ##
==========================================
+ Coverage   84.59%   84.60%   +0.01%     
==========================================
  Files         139      139              
  Lines       11223    11231       +8     
  Branches      636      637       +1     
==========================================
+ Hits         9494     9502       +8     
  Misses       1729     1729              

Files Changed	Coverage Δ
lib/components/SInputCheckbox.vue	100.00% <100.00%> (ø)

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[kiaking]

I like the overall API design 👍

[brc-dd]

There is a bit of issue. Technically indeterminate should work same as false. I'll update the logic a bit and resolve conflicts.

[kiaking]

Thanks a bunch! Working beautiful 👍