Fix ErrorFallback type compatibility with react-error-boundary 6.1.0

[Copilot]

Problem

TypeScript compilation fails after updating react-error-boundary to 6.1.0 and @types/react to 19.2.9. The FallbackProps.error type changed from Error to unknown, breaking the ErrorFallback component signature.

Changes

Updated ErrorFallback component (src/main.tsx):

• Changed error parameter type from Error to unknown
• Added type guard to safely extract error message

Updated dependencies:

• react-error-boundary: 6.0.3 → 6.1.0
• @types/react: 19.2.8 → 19.2.9

Implementation

// Before
function ErrorFallback({ error }: { error: Error }): React.ReactElement {
  return <pre>{error.message}</pre>;
}

// After
function ErrorFallback({ error }: { error: unknown }): React.ReactElement {
  const errorMessage = error instanceof Error ? error.message : String(error);
  return <pre>{errorMessage}</pre>;
}

The type guard maintains runtime safety while satisfying the stricter type constraints from the library update.

Original prompt

fix problem with PR

game-app@1.2.19 build
tsc -b && vite build

Error: src/main.tsx(26,20): error TS2322: Type '({ error }: { error: Error; }) => ReactElement<unknown, string | JSXElementConstructor>' is not assignable to type 'ComponentType'.
Type '({ error }: { error: Error; }) => ReactElement<unknown, string | JSXElementConstructor>' is not assignable to type 'FunctionComponent'.
Types of parameters '__0' and 'props' are incompatible.
Type 'FallbackProps' is not assignable to type '{ error: Error; }'.
Types of property 'error' are incompatible.
Type 'unknown' is not assignable to type 'Error'.
Error: Process completed with exit code 1.

#421

and update

Updates react-error-boundary from 6.0.3 to 6.1.0

Release notes
Commits

Updates @types/react from 19.2.8 to 19.2.9

Commits

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[pethers]

@copilot always use strict typing for code and test

Run npm run build

game-app@1.2.19 build
tsc -b && vite build

Error: src/main.tsx(26,20): error TS2322: Type '({ error }: { error: Error; }) => ReactElement<unknown, string | JSXElementConstructor>' is not assignable to type 'ComponentType'.
Type '({ error }: { error: Error; }) => ReactElement<unknown, string | JSXElementConstructor>' is not assignable to type 'FunctionComponent'.
Types of parameters '__0' and 'props' are incompatible.
Type 'FallbackProps' is not assignable to type '{ error: Error; }'.
Types of property 'error' are incompatible.
Type 'unknown' is not assignable to type 'Error'.
Error: Process completed with exit code 1.