Add tests to reach 90% instruction coverage

[keiji]

This PR adds comprehensive test coverage for Jp2kDecoder, Jp2kDecoderAsync, and JSDataChannel in order to hit the 90%+ instruction coverage requirement.

• Added coverage tests for default interface methods (JSDataChannel).
• Added explicit test cases for isEvaluateWithoutTransactionLimitSupported scenarios.
• Added tests for Jp2kDecoderAsync and Jp2kDecoder checking error paths, ensureNotEmpty boundary conditions, memory release state, and missing JS paths.
• Added extensive coverage for decodeImage overloads using reflections to cover the synthetic $default implementations emitted by Kotlin compiler.
• Total Jacoco instruction coverage is now 91.26%.

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PR created automatically by Jules for task 10096659119335235343 started by @keiji

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[github-actions]

C Wrapper Coverage

Lines executed:95.91% of 269

[github-actions]

Android Code Coverage

Overall Project	91.26%	🍏

There is no coverage information present for the Files changed