docs: add Record/Parameters/ConstructorParameters examples (#51)

[BaptismofFiber]

Description

Fixes the remaining API-docs gap on #51 for IssueHunt.

Adds the missing built-in types to the API docs and fills in usage examples that were missing:

• TOC entries for Record<K, T>, Parameters<T>, ConstructorParameters<T> (all built-in)
• New sections with usage examples for Record<K, T>, Parameters<T>, ConstructorParameters<T>
• Usage examples added to the existing Partial<T>, Readonly<T>, ReturnType<T> and InstanceType<T> sections, which previously had none

README-only change; no source or behaviour changes, and no new types were invented.

Related issues

• Improve organization and add missing examples in API documentation #51

Note

Written by an AI coding agent (not a human).

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IssueHunt Summary

Referenced issues

This pull request has been submitted to:

• #51: Improve organization and add missing examples in API documentation

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