[DNM] Allow "experimental-auto" idivf

[mattwthompson]

• Tag issue being addressed
• Add tests
• Update docstrings/documentation, if applicable
• Lint codebase
• Update changelog

[codecov]

Codecov Report

❌ Patch coverage is 40.00000% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.48%. Comparing base (5ffcb58) to head (ef6a695).
⚠️ Report is 190 commits behind head on main.

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[j-wags]

Looks solid to me and I saw a presentation from @ntBre this morning using this experimental functionality, so I assume there aren't glaring errors. IIRC, this is the first time that we're introducing an indexed parameter that could be int or string. I'd approve this pending adding tests that ensure setters and getters do sane things, including being set to int/string while being accessed both as parameter.idivf[N] and parameter.idivfN.

[mattwthompson]

Closing until we start working on this again