Allow pool metadata to display UTF-8 emojis

[ArthurHoeke]

Currently Polkadot-js allows for UTF-8 emojis to be displayed on both the validators page and address identities. However, the pools page currently strips any non-standard characters from pool names.

For consistency this pull request adjusts the transformName regex to allow for UTF-8 emojis, as is also the case on staking.polkadot.network/#/pools.

[jacogr]

Identities -

• don't show emojis when the identity has not been approved
• do show emojis when the identity is deemed at least reasonable by a registrar

aka not by default until it is deemed "non-spam" and viable.

There is no built-in spam/frustration filter on these specific user inputs, hence the filter applied here.

[ArthurHoeke]

Identities -

• don't show emojis when the identity has not been approved
• do show emojis when the identity is deemed at least reasonable by a registrar

aka not by default until it is deemed "non-spam" and viable.

There is no built-in spam/frustration filter on these specific user inputs, hence the filter applied here.

How about allowing say up to 4 emoji's to prevent spam and maybe filtering out any unwanted ones? As of right now a bad actor could already put anything they'd want in the pool metadata, don't think there are that many potentially bad emojis out there.

function transformName(input: string): string {
  const naughtyEmojis = ['🔫','💩','☠️','🍆'];

  let sanitizedInput = input.replace(new RegExp(naughtyEmojis.join('|'), 'g'), '');

  const emojiRegex = /([\uD800-\uDBFF][\uDC00-\uDFFF]|[^\x20-\x7E\uD83C-\uDBFF\uDC00-\uDFFF])/g;
  const emojis = sanitizedInput.match(emojiRegex) || [];
  const limitedEmojis = emojis.slice(0, 4);

  emojis.forEach((emoji, index) => {
    sanitizedInput = sanitizedInput.replace(emoji, index < 4 ? limitedEmojis[index] : '');
  });

  return sanitizedInput;
}

Also taking into account that a bad actor could lose their initial minimum bond of 500 DOT.