docs: clarify output_dir behavior in medication_examples.md

[kleeena]

This PR updates the code example in docs/examples/medication_examples.md to clarify how the output_dir parameter affects where the output file is saved when using lx.io.save_annotated_documents.

What's Changed

• Explicitly sets output_dir="." in the example to ensure the file is saved in the current working directory.
• Adds comments and a note explaining that the default value of output_dir is test_output/, which may not match user expectations.

Why This Matters

The previous example could confuse users, as it implied that setting output_name alone controls the full file path. In practice, the file is saved to the test_output/ directory by default. This clarification improves usability and prevents unnecessary debugging.

Related Issue

Fixes #8

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[aksg87]

Hi @kleeena,

Thanks for addressing this issue with the documentation. One suggestion - I think we can remove the inline comment since the output_dir="." is self-explanatory:

lx.io.save_annotated_documents(
    [result],
    output_name="medical_ner_extraction.jsonl",
    output_dir="."
)

Otherwise LGTM! Thanks for improving the documentation.