[WIP] Port TypeScript PR #60195: Assume that type node annotations resolving to error types can be reused

[Copilot]

Port TypeScript PR #60195: Assume that type node annotations resolving to error types can be reused

Plan:

• Analyze the original TypeScript PR changes
• Locate the equivalent Go code in internal/checker/nodebuilderimpl.go
• Identify the exact function and location for the change
• Add error type check in tryReuseExistingNonParameterTypeNode function
• Build and test the change
• Run baseline tests and accept changes
• Validate the fix works correctly

Change Details:

The original TypeScript PR adds a check in the type node reuse logic to allow reusing type nodes that resolve to error types. This prevents cascading errors in isolatedDeclarations when there are already type errors in the source.

In the Go port, this needs to be added in internal/checker/nodebuilderimpl.go in the tryReuseExistingNonParameterTypeNode function, right after the annotationType = b.getTypeFromTypeNode(existing, true) call.

Fixes #1118.

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[weswigham]

In the go port, this codepath is untested and unused at present, along with all the nodebuilder node-reuse logic, so can't be verified as doing that the original PR intended until that's in.