fix: use method of largest remainder to count poll votes

[Antreesy]

☑️ Resolves

• Fix Poll rounding error #11867
• Ref https://en.wikipedia.org/wiki/Quota_method
  • Rounds up total to 100% for most cases. Keeps it lower if there is no possibility to add up to equally high values

🖌️ UI Checklist

🖼️ Screenshots / Screencasts

🏚️ Before	🏡 After

🏁 Checklist

• 🌏 Tested with different browsers / clients:
  • Chromium (Chrome / Edge / Opera / Brave)
  • Firefox
  • Safari
  • Talk Desktop
  • Not risky to browser differences / client
• 🖌️ Design was reviewed, approved or inspired by the design team
• ⛑️ Tests are included or not possible
• 📗 User documentation in https://github.com/nextcloud/documentation/tree/master/user_manual/talk has been updated or is not required

[DorraJaouad]

Quota methods is a good solution, yet I'd recommend to simplify its implementation for a better understanding

    if (!total) {
        return votes
    }

    const { wholes, remainders } = votes.reduce((acc: VoteAccumulator, vote) => {
        const quota = vote / total * 100
        acc.wholes.push(Math.floor(quota))
        acc.remainders.push(quota % 1)
        return acc
    }, { wholes: [], remainders: [] })

    // Calculate the sum of whole parts
    const sumWholes = wholes.reduce((acc, value) => acc + value, 0)

    // If the sum of whole parts is already 100, return it
    if (sumWholes === 100) {
        return wholes
    }

    // Calculate how many more votes we need to reach 100
    let remainingVotes = 100 - sumWholes

    // Get the indexes of the largest remainders
    const largestRemainders = remainders
        .map((value, index) => ({ value, index }))
        .sort((a, b) => b.value - a.value)
        .slice(0, remainingVotes)
        .map(item => item.index)

    // Distribute the remaining votes
    for (const index of largestRemainders) {
        wholes[index]++
    }

    return wholes

[Antreesy]

// If the sum of whole parts is already 100, return it

Almost never the case, unless you have exactly 1,2,4,5,10,20,50 or 100 votes. Math.round is better here
But since Math.round is almost always the case, maybe I can move some calculations after this return

// Distribute the remaining votes

That rounds until 100%, but that's exactly the possible error for equal remainders described in the issue:

[DorraJaouad]

Tested, we agreed to prioritize fair accuracy than mainly targeting 100%.

[Antreesy]

/backport to stable30