feat: Support FormProvider

[zombieJ]

• Support global validateMessages config.
• Support communication between forms.

Preview

📸 Context Demo

Document

📖 https://github.com/react-component/field-form/blob/context/README.md#formprovider

[vercel]

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[codecov]

Codecov Report

Merging #4 into master will increase coverage by 0.44%.
The diff coverage is 46.55%.

@@            Coverage Diff             @@
##           master       #4      +/-   ##
==========================================
+ Coverage   16.27%   16.72%   +0.44%     
==========================================
  Files          11       13       +2     
  Lines         590      616      +26     
  Branches       99      110      +11     
==========================================
+ Hits           96      103       +7     
- Misses        494      510      +16     
- Partials        0        3       +3

Impacted Files	Coverage Δ
src/useForm.ts	24.51% <0%> (ø)	⬆️
src/index.tsx	100% <100%> (+31.42%)	⬆️
src/FormContext.tsx	16.66% <16.66%> (ø)
src/Form.tsx	59.45% <59.45%> (ø)
src/Field.tsx	1.45% <0%> (ø)	⬆️

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[zombieJ]

Please feel free if current context api design should update. @afc163

[afc163]

rules 是不是也可以支持一下。

https://redd.gitbook.io/react-advanced-form/components/form-provider

[zombieJ]

Rule 我们现在是 Field level 的，不太好支持。