Improve TypeScript type definitions in jest.d.ts

[Rezakarimzadeh98]

Summary

This PR improves TypeScript type definitions in scripts/jest/typescript/jest.d.ts to provide better type safety and IntelliSense support for React's internal test suite.

Changes

• Add generic type parameters to expect() and Expect interface for better type inference
• Add proper function signatures for test lifecycle functions (beforeEach, afterEach, etc.)
• Add type-safe generic spy functions (spyOnDev, spyOnProd) with keyof constraints
• Convert deprecated Object type to lowercase object (TypeScript best practice)
• Fix parameter names (arguments → args to avoid reserved keyword)
• Add generic type parameter to MockFunction interface

Benefits

• Better IntelliSense: Autocomplete shows correct types when writing tests
• Catch errors early: TypeScript catches type mismatches at compile time
• Modern TypeScript: Uses current best practices and conventions
• Zero runtime impact: Pure compile-time improvement with no breaking changes

Testing

• ✅ ESLint passes with no errors
• ✅ TypeScript compilation successful
• ✅ No breaking changes - fully backward compatible

Example

// Before: No type safety
const spy = spyOnDev(MyObject, 'myMethod'); // Returns 'any'

// After: Full type safety
const spy = spyOnDev(MyObject, 'myMethod'); // Fully typed with autocomplete
//                            ^^^^^^^^ TypeScript ensures this key exists

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