Add 91 comprehensive React interview questions covering modern React features

[0xsatoshi99]

Summary

This PR adds 91 comprehensive React interview questions (Q90-Q180) covering modern React features, hooks, performance optimization, and best practices.

Fixes

Closes #238 - Clarifies the differences between Decorators and Higher-Order Components, plus adds extensive modern React coverage

Changes

Topics Covered:

React Hooks (Q90-Q99):

• useState vs useReducer
• useEffect vs useLayoutEffect
• useContext for context consumption
• useMemo and useCallback for performance
• useRef for DOM access and mutable values
• useImperativeHandle for ref customization
• Custom Hooks creation and patterns
• React.memo vs useMemo

Modern React 18 Features (Q100-Q106):

• React Server Components
• Concurrent Rendering
• useTransition for non-urgent updates
• useDeferredValue for deferred rendering
• useId for stable IDs
• useSyncExternalStore for external stores
• useInsertionEffect for CSS-in-JS
• Automatic Batching

Component Patterns (Q107-Q120):

• Suspense for code splitting and data fetching
• Error Boundaries
• React.lazy and code splitting
• Controlled vs Uncontrolled components
• HOC vs Render Props (addresses issue What is the difference between Decorators and HOCs? #238)
• forwardRef for ref forwarding
• Component vs PureComponent
• createElement vs cloneElement
• React.Children utilities

Performance Optimization (Q121-Q130):

• React.memo for component memoization
• useMemo for value memoization
• useCallback for function memoization
• Code splitting strategies
• Tree shaking
• Lazy loading
• When NOT to use memoization
• Performance bottlenecks

Core Concepts (Q131-Q150):

• State vs Props
• Prop drilling and solutions
• Synthetic events vs native events
• Event pooling (removed in React 17)
• JSX vs createElement
• Virtual DOM and reconciliation
• Keys and refs
• Lifting state up
• Composition vs inheritance
• Lifecycle methods and Hook equivalents

Context and State Management (Q146-Q148):

• React Context API
• Context performance implications
• Context vs Redux

Routing and Navigation (Q149-Q150):

• React Router basics
• BrowserRouter vs HashRouter

Testing and Debugging (Q151, Q175-Q179):

• React Testing Library best practices
• React DevTools
• Profiler API
• Development vs production builds
• Debugging techniques

Rendering Strategies (Q157-Q159):

• Server-Side Rendering (SSR)
• Static Site Generation (SSG)
• Incremental Static Regeneration (ISR)
• Hydration process

Styling (Q160-Q162):

• Different styling approaches
• CSS-in-JS pros and cons
• Inline styles vs CSS classes

Advanced Topics (Q163-Q180):

• Code splitting and tree shaking
• Shallow vs deep comparison
• Immutability importance
• Form handling
• React vs Vue vs Angular
• Portals
• React Fiber architecture
• StrictMode
• PropTypes vs TypeScript

Decorators vs HOCs (Q123):

• Directly addresses issue What is the difference between Decorators and HOCs? #238
• Explains decorators as syntactic sugar for HOCs
• Clarifies that decorators are experimental
• Notes that modern React prefers Hooks over both patterns
• Provides clear examples of each approach

Quality

✅ All 91 questions include:

• Clear, concise answers
• Practical explanations
• Real-world use cases
• Best practices
• Common pitfalls
• Modern React 18+ features
• Performance considerations

Statistics

• Lines added: 548
• New questions: 91 (Q90-Q180)
• Topics covered: 25+ major React areas
• React versions: Covers React 16.8+ through React 18

Educational Value

This contribution significantly enhances the repository by:

• Doubling the number of questions (from 89 to 180)
• Covering modern React features (Hooks, Concurrent Mode, Server Components)
• Providing comprehensive performance optimization guidance
• Explaining component patterns and best practices
• Addressing the specific issue What is the difference between Decorators and HOCs? #238 about Decorators vs HOCs
• Including testing and debugging strategies
• Covering different rendering strategies (SSR, SSG, ISR)

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Note: This PR directly addresses issue #238 by clarifying the differences between Decorators and HOCs in Q123, while also providing extensive coverage of modern React development practices.