feat: generate kcl data from json

[jakezhu9]

1. Does this PR affect any open issues?(Y/N) and add issue references

• N
• Y

part of kcl-lang/kcl#526

2. What is the scope of this PR (e.g. component or file name):

pkg/tools/gen

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

Add the feature to generate kcl code from json. You can find an example in testdata/json. Additionally, I made the following changes:

• Improve the auto mode selection to supports more modes and provides better accuracy.
• Change kclSchema struct to kclFile. It now contains all the imports, schemas and data in a kcl file. We can handle and render them using the same method genKcl
• Refactor formatDoc function to indentLines for better readability and reusability. Also add some template functions like include to help render the output.

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[coveralls]

Pull Request Test Coverage Report for Build 6011772544

• 69 of 81 (85.19%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.4%) to 64.545%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/tools/gen/template.go	25	27	92.59%
pkg/tools/gen/genkcl.go	9	13	69.23%
pkg/tools/gen/genkcl_json.go	31	37	83.78%

Totals
Change from base Build 6000403335:	0.4%
Covered Lines:	2525
Relevant Lines:	3912

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💛 - Coveralls

[Peefy]

LGTM