Error handling test

[johnfav03]

Fixes #

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[Copilot]

Pull Request Overview

This PR adds a new TypeScript compiler error that prevents comparison operations (except equality) between string literals. The change introduces validation to catch potentially problematic string literal comparisons during compilation.

Key changes:

• Adds a new error diagnostic for string literal comparisons
• Implements compiler logic to detect and report string literal comparison operations
• Creates test case to validate the new error behavior

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 2 comments.

File	Description
tests/cases/compiler/StringComp.ts	Test case demonstrating string literal comparison that should trigger the new error
tests/baselines/reference/stringComp.*	Baseline files for the new compiler test (types, symbols, and JS output)
src/compiler/diagnosticMessages.json	New error message for string literal comparison restriction
src/compiler/checker.ts	Compiler logic to detect and report string literal comparison errors

Comments suppressed due to low confidence (2)

[Copilot]

The baseline file references 'stringComp.ts' but the actual test file is named 'StringComp.ts', creating a mismatch that will cause test failures.

Suggested change

	//// [tests/cases/compiler/stringComp.ts] ////
	=== stringComp.ts ===
	//// [tests/cases/compiler/StringComp.ts] ////
	=== stringComp.ts ===

[Copilot]

The baseline file references 'stringComp.ts' but the actual test file is named 'StringComp.ts', creating a mismatch that will cause test failures.

Suggested change

	//// [tests/cases/compiler/stringComp.ts] ////
	//// [stringComp.ts]
	//// [stringComp.js]
	//// [tests/cases/compiler/StringComp.ts] ////
	//// [StringComp.ts]
	//// [stringComp.js]