How to fix Default type of constructor property must be assignable to its declared type in TypeScript

// ERROR: Default type 'number' is not assignable to declared type 'string'
class User {
  constructor(
    public name: string = 123  // WRONG - default is number, not string
  ) {}
}

// CORRECT - default value matches declared type
class User {
  constructor(
    public name: string = "Guest"  // OK - both are string
  ) {}
}

// CORRECT - number default for number type
class Counter {
  constructor(
    public count: number = 0  // OK - both are number
  ) {}
}

// ERROR - null not assignable to string
class User {
  constructor(
    public email: string = null  // WRONG
  ) {}
}

// CORRECT - include null in type
class User {
  constructor(
    public email: string | null = null  // OK - null is now valid
  ) {}
}

// OR use undefined for optional
class User {
  constructor(
    public email?: string  // OK - implicitly string | undefined, no default needed
  ) {}
}

type Status = "active" | "inactive" | "pending";

// ERROR - "unknown" is not in the Status union
class Account {
  constructor(
    public status: Status = "unknown"  // WRONG
  ) {}
}

// CORRECT - use a valid literal from the union
class Account {
  constructor(
    public status: Status = "pending"  // OK - "pending" is in Status
  ) {}
}

interface Config {
  host: string;
  port: number;
}

// ERROR - missing required property 'port'
class Server {
  constructor(
    public config: Config = { host: "localhost" }  // WRONG
  ) {}
}

// CORRECT - include all required properties
class Server {
  constructor(
    public config: Config = { host: "localhost", port: 3000 }  // OK
  ) {}
}

// With explicit type - must match
class Settings {
  constructor(
    public timeout: number = 5000  // type must be number
  ) {}
}

// Let TypeScript infer - type becomes number from default
class Settings {
  constructor(
    public timeout = 5000  // inferred as number
  ) {}
}

interface ComplexConfig {
  [key: string]: string | number;
}

// If TypeScript has trouble inferring
class App {
  constructor(
    public config: ComplexConfig = { timeout: 1000 } as ComplexConfig
  ) {}
}

{
  "compilerOptions": {
    "strict": true,           // Enables all strict checks
    "strictNullChecks": true  // null/undefined must be explicit in types
  }
}

// With strict mode OFF - this might work
class User {
  constructor(public name: string = null) {}  // null might be allowed
}

// With strict mode ON - must be explicit
class User {
  constructor(public name: string | null = null) {}  // OK - null is allowed
}