Add boundary tests for JsonTreeWriter.endArray() error handling

[lmj798]

Summary

Add 3 boundary tests for JsonTreeWriter.endArray() to verify proper exception throwing when called in invalid states:

1. testEndArrayOnEmptyStackThrows - Verifies IllegalStateException when calling endArray() on empty stack
2. testEndArrayWithPendingNameThrows - Verifies IllegalStateException when a pending name exists (object not closed)
3. testEndArrayWhenStackTopIsNotArrayThrows - Verifies IllegalStateException when stack top is an object, not an array

Why

Current tests cover:

• Normal array/object begin/end operations
• Close after write
• Premature close
• Null handling
• NaN/Infinity handling
  However, they don't explicitly test endArray() error conditions for invalid state detection. These boundary cases ensure proper state validation and prevent regressions from state management changes.

Verification

mvn -Dtest=JsonTreeWriterTest test
Result: Tests run: 25, Failures: 0, Errors: 0, Skipped: 0 - BUILD SUCCESS

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[eamonnmcmanus]

This seems like a reasonable change. Just one question.

[Marcono1234]

Could you please move your last commit (073d0f5) to a separate PR? It is unrelated to JsonTreeWriter.endArray().

[lmj798]

Could you please move your last commit (073d0f5) to a separate PR? It is unrelated to JsonTreeWriter.endArray().

Sorry about that, and thank you for catching it.
You’re absolutely right that commit 073d0f5 was unrelated. I’ve moved it to a separate PR and force-pushed this branch, so this PR now only contains the JsonTreeWriter.endArray() changes.

[eamonnmcmanus]

Thanks, it's good to check these extra cases.