Add triple colon support ::: for the CalloutExtension

[ifiokjr]

Description

• Add support for typing ::: to create a default CalloutExtension.
• Add support for typing :::success to create a named CalloutExtension with the class info.
• Add support for restricting the types of callouts that can be created.
• Add support for icons to the callout extension.

Context

The code would look very similar to the code used for the CodeBlockExtension for pressing the enter key after typing the :::. An input rule could also be used to handle pressing the space key as seen in the same code block extension.

remirror/packages/@remirror/extension-code-block/src/code-block-extension.ts

Lines 193 to 201 in f7778cc

	nodeInputRule({
	regexp,
	type: this.type,
	beforeDispatch: ({ tr, start }) => {
	const $pos = tr.doc.resolve(start);
	tr.setSelection(new TextSelection($pos));
	},
	getAttributes: getAttributes,
	}),

[ifiokjr]

Kinda done, in the beta.