docs: restrict string's length for openAPI SDK to prevent API rejection

[afsuyadi]

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Changes

Closes #7995

1. Use existing constant TRAIT_STRING_VALUE_MAX_LENGTH to restrict the string's length.
2. Build a function for post-processing the hook and detecting trait_value to return the desired result
3. Call the function during API calling
4. Update yaml file with maxLength

How did you test this code?

1. Build unit tests with various schemas to ensure reliable results

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[coderabbitai]

📝 Walkthrough

Walkthrough

Adds an OpenAPI post-processing hook that applies TRAIT_STRING_VALUE_MAX_LENGTH to the string variant of trait_value schemas. Registers the hook in the API settings, adds unit tests for matching and absent schema cases, and updates the generated OpenAPI specification for identity trait request and response schemas with maxLength: 2000.

Estimated code review effort: 3 (Moderate) | ~20 minutes

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[coderabbitai]

Actionable comments posted: 1

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ℹ️ Review info

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📥 Commits

Reviewing files that changed from the base of the PR and between e55b56d and 231c559.

📒 Files selected for processing (4)

• api/api/openapi.py
• api/app/settings/common.py
• api/tests/unit/api/test_unit_openapi.py
• sdk/openapi.yaml

[coderabbitai]

🎯 Functional Correctness | 🔵 Trivial | ⚡ Quick win

Cover both request and response trait schemas.

This test exercises only TraitInput, while the contract also requires Trait.trait_value to be constrained. Add a second matching component, or assert the generated schema, so the traversal cannot regress to updating only the request schema.