Add documentation on output files (new page), add links to maritime s…

[StephanieKemna]

…chema, add links to input/output file pages from usage page

Resolves #71

[Copilot]

Pull Request Overview

This PR adds comprehensive documentation for output files by creating a new dedicated page and improves navigation between related documentation sections. The changes resolve issue #71 by documenting the maritime schema format used for output files and adding cross-references.

• Creates a new output_files.rst page with detailed documentation and example JSON output
• Adds cross-reference links between input/output file pages and the usage page
• Restructures the usage page to better organize input and output information

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
docs/source/output_files.rst	New documentation page explaining output file format with maritime schema links and example JSON
docs/source/usage.rst	Updated to add cross-references and reorganize input/output sections
docs/source/input_files.rst	Added reference label for cross-linking
docs/source/index.rst	Added new output_files page to table of contents

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[tomarnepedersen]

Looks good