feat: impl scalar yaml stream output

[Peefy]

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

• feat: impl scalar yaml stream output

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

• kclvm/runtime/src/value/val_is_in.rs
• kclvm/runtime/src/value/val_plan.rs

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

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

• test/grammar/builtins/manifests/yaml_stream/**

[coveralls]

Pull Request Test Coverage Report for Build 8029658496

Details

• -6 of 10 (40.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.006%) to 71.914%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
kclvm/runtime/src/value/val_plan.rs	4	6	66.67%
kclvm/runtime/src/value/val_is_in.rs	0	4	0.0%

Totals
Change from base Build 8029376640:	-0.006%
Covered Lines:	44243
Relevant Lines:	61522

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💛 - Coveralls