Create JOSS Submission Branch

[tinaok]

Description:
To prepare for submitting healpix-convolution to the Journal of Open Source Software (JOSS), we need to create a dedicated branch and add the necessary submission files.

Tasks:

• Create a joss-submission branch.

• Add a paper.md following JOSS guidelines (title, summary, statement of need, figures, references, etc.).

• Include a paper.bib file for references.

• Ensure the repository has appropriate documentation (README, installation guide, examples).

• Check that the software meets JOSS requirements (e.g., tests, license, DOI if applicable).

• Submit a pre-review to JOSS before the final submission.

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References:

• JOSS Submission Guide: https://joss.theoj.org/about
• JOSS Review Criteria: https://joss.theoj.org/review_criteria.html