feat: more efficient text-only fragments

[Rich-Harris]

small tweak: we can make text-only fragments (like {#if true}hello!{/if}) more efficient by creating the text node directly, rather than cloning a fragment. Also the sequence.length === 1 special case isn't really doing anything for us, so we can simplify the code a bit

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Latest commit: 2dd0901

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[Rich-Harris]

Added a second optimisation:

<p>{location.href}</p>

-var root = $.template(`<p> </p>`); +var root = $.template(`<p></p>`); export default function Main($$anchor) { var p = root(); - var text = $.child(p); - text.nodeValue = location.href; - $.reset(p); + p.textContent = `${location.href ?? ""}`; $.append($$anchor, p); }