avoid `any` type usage

Replace any type annotations with more specific types to improve type safety and null handling. The any type disables TypeScript’s type checking, including null safety checks, making code prone to runtime errors.

Use unknown as a safer alternative when the type is truly unknown, as it requires type checking before use. When possible, use specific types like ReactNode, interfaces, or union types that accurately describe the expected values.

Example progression from unsafe to safe typing:

// Avoid: Disables all type checking
let resolve: (value?: any) => void;

// Better: Requires type checking before use  
let resolve: (value?: unknown) => void;

// Best: Use specific types when known
let resolve: (value?: void) => void;

// For React components, use specific types
readonly unstable__transformChildren?: (children: ReactNode) => ReactNode;

This approach prevents null reference errors by ensuring TypeScript can properly track nullable and undefined values through the type system.