Port TypeScript PR #60083: Don't issue implicit any when obtaining the implied type for a binding pattern

[Copilot]

This PR ports TypeScript PR #60083 to prevent inappropriate implicit any errors when obtaining the implied type for binding patterns in destructuring scenarios.

Problem

Previously, binding patterns in destructuring parameter declarations would incorrectly trigger implicit any errors, even when the types could be properly inferred from context. For example:

/**
 * @param {Object} [config]
 * @param {Partial<Record<'json' | 'jsonc' | 'json5', string[]>>} [config.additionalFiles]
 */
export function prepareConfig({
    additionalFiles: {
        json = []  // ❌ Error: Binding element 'json' implicitly has an 'any[]' type
    } = {}
} = {}) {
    json // Should be inferred as string[]
}

Solution

The fix separates the core type widening logic from implicit any reporting by:

1. Extracting core logic: Created new function getWidenedLiteralTypeForInitializer that contains only the type widening logic without implicit any reporting
2. Updating existing function: Modified widenTypeInferredFromInitializer to delegate to the new function
3. Using appropriate function: Updated getTypeFromBindingElement to call getWidenedLiteralTypeForInitializer directly when obtaining implied types for binding patterns

Changes Made

• Added getWidenedLiteralTypeForInitializer() function in internal/checker/checker.go
• Updated widenTypeInferredFromInitializer() to use the new function
• Modified getTypeFromBindingElement() to call the new function for binding pattern type inference

Testing

All existing tests pass, including the specific test cases from the original TypeScript issue:

• destructuringParameterDeclaration9 (JavaScript with JSDoc types)
• destructuringParameterDeclaration10 (TypeScript with explicit types)

The fix correctly removes the inappropriate implicit any errors while preserving proper type inference and other error reporting.

Fixes #1116.

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