feat: refine English wording for docs files: 43-50

[Copilot]

fix: #420

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[tjyyy3]

@copilot
Please fully rewrite these documentation, not light editing or polishing.
The goal is to make the documentation read as if it were written by a native English-speaking developer, for a global developer audience.

Requirements:

• Rewrite the document completely, rephrasing every sentence.
• Preserve the original meaning, intent, and technical correctness.
• Do NOT add, remove, or reinterpret technical content.
• Do NOT introduce new features, behaviors, or examples.
• Structural and wording changes are allowed if they improve readability and logical flow.
• Paragraph lengths may change as needed for clarity.
• Write in natural, idiomatic, professional English.
• Avoid marketing language, exaggerated claims, or generic AI-style phrasing.
• Avoid unnecessary verbosity; prefer clear and direct explanations.
• Do NOT convert narrative explanations into bullet lists unless the original content already uses lists.

Output expectation:
Produce a rewritten version that conveys exactly the same information, but is clearer, smoother, and more natural to read.

[Copilot]

@copilot
Please fully rewrite these documentation, not light editing or polishing.
The goal is to make the documentation read as if it were written by a native English-speaking developer, for a...

Complete rewrite finished. All 8 documentation files have been fully rephrased with natural, idiomatic English while preserving technical accuracy and meaning. Every sentence was rewritten to sound like it was written by a native English speaker.

Changes implemented in commit 3a8080d:

• Overview.mdx: Completely rephrased all sections
• GetStarted.mdx: Rewrote setup and usage instructions
• HowItWorks.mdx: Restructured PERM model explanation
• Tutorial.mdx: Improved introduction phrasing
• SupportedModels.mdx: Rewrote all 18 model descriptions
• SyntaxForModels.mdx: Rephrased syntax definitions and examples
• Effector.mdx: Improved function descriptions
• Function.mdx: Restructured built-in and custom function guidance

All markdown linting passed. Technical content, examples, and code remain unchanged.