refactor(json-schema): refactor stringify type to fix literal type is erased

[liuweiGL]

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解决的问题

SchemaField 中的 component 跟 decorator 属性类型被 stringify 抹掉了。

修复之前的效果

修复之后效果

[codecov-commenter]

Codecov Report

Merging #1508 (f75345c) into formily_next (4c098d2) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##           formily_next    #1508      +/-   ##
================================================
- Coverage         89.50%   89.50%   -0.01%     
================================================
  Files               137      137              
  Lines              6004     6067      +63     
  Branches           1529     1550      +21     
================================================
+ Hits               5374     5430      +56     
- Misses              627      632       +5     
- Partials              3        5       +2     

Impacted Files	Coverage Δ
...ckages/reactive-vue/src/observer/observerInVue2.ts	95.45% <0.00%> (-4.55%)	⬇️
packages/vue/src/components/Field.ts	95.65% <0.00%> (-4.35%)	⬇️
packages/vue/src/components/ArrayField.ts	96.00% <0.00%> (-4.00%)	⬇️
packages/vue/src/components/ObjectField.ts	96.00% <0.00%> (-4.00%)	⬇️
packages/vue/src/components/RecursionField.ts	72.00% <0.00%> (-1.12%)	⬇️
packages/validator/src/parser.ts	86.44% <0.00%> (-0.23%)	⬇️
packages/path/src/types.ts	100.00% <0.00%> (ø)
packages/core/src/shared/index.ts	100.00% <0.00%> (ø)
packages/reactive/src/reaction.ts	95.30% <0.00%> (ø)
packages/vue/src/shared/context.ts	100.00% <0.00%> (ø)
... and 17 more

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