🧪 Add test coverage for JAXTracer

[harshithluc073]

🎯 What: The testing gap addressed
The codebase was missing tests for the JAXTracer module.

📊 Coverage: What scenarios are now tested
Tests for attaching to/detaching from a callable, raising correct errors on invalid attachments (e.g., non-callables or double attaches), and successfully capturing the graph and output tensor metadata on a simple JAX function.

✨ Result: The improvement in test coverage
The codebase now has basic test coverage for the JAXTracer matching the patterns seen in test_pytorch_tracer.py. This ensures it operates as expected against JAX function tracing.

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PR created automatically by Jules for task 10390887178547093621 started by @harshithluc073

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