Refactored FORTRAN module

[Montana]

• Clearer formatting and indentation.
• Refactored repetitive code using associate.
• Added inline comments for clarity.
• Enhanced readability and consistency.

[bonachea]

Hi @Montana, thanks for reaching out and we generally do appreciate genuine community contributions.

Unfortunately this PR seems to propose purely cosmetic/syntactic changes, with no real semantic content. It looks like the work was probably done with an automated tool, and (aside from a few very minor new comments) provides no obvious maintainability benefit. It also modifies only one test in a larger suite of tests, and additionally has conflicts with some other changes already merged (PR #174) and in-flight (PRs #169 and #158) for the target branch.

Declined without prejudice.