refactor: improve ranked choice voting readability and add test

[wa0x6e]

This PR improves comprehension of the ranked choice voting system by adding more documentation, and add more test.

Add more docs

Add more docs to some function, to help comprehension, and understand returned value.

Add more tests

Add more tests, justifying that the fix #1176 is really needed, and not just an edge case.

This fix is not related to invalid votes, etc..., the scenario can happen if the irv function pass on the first round, and the first round do no contain all the votes.

Adjust getChoiceString

Update function to handle invalid choice: they're now ignored, instead of showing undefined, like on the approval/quadratic/weighted voting system.

This is consistent with the score computation, where those invalid votes are already ignored

[Copilot]

Pull Request Overview

This pull request refactors the ranked choice voting implementation to improve code readability through better documentation and function naming. It also adds comprehensive test coverage for edge cases and the newly exported getFinalRound function.

Key changes:

• Improved function naming and added extensive JSDoc documentation for better API clarity
• Exported getFinalRound function and added comprehensive test coverage for IRV algorithm edge cases
• Enhanced getChoiceString method to properly handle invalid choice indices using filter instead of conditional mapping

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/voting/rankedChoice.ts	Adds comprehensive JSDoc documentation, renames functions for clarity, exports getFinalRound, and improves getChoiceString implementation
src/voting/rankedChoice.spec.js	Adds extensive test coverage for getFinalRound function, isValidChoice validation, and edge cases including invalid choice indices

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[Copilot]

Exporting getFinalRound creates a breaking change to the module's public API. Consider whether this function should be exported or if it's intended for internal use only.

Suggested change

	export function getFinalRound(
	function getFinalRound(

[wa0x6e]

Not an important PR, don't need a release after merge, can wait next fix/feature

[ChaituVR]

tAck