xst 8.8.0

Features:

• Optional catch binding
• JSON superset
• Symbol.prototype.description
• Function.prototype.toString revision
• Object.fromEntries
• Well-formed JSON.stringify
• String.prototype.{trimStart,trimEnd}
• Array.prototype.{flat,flatMap}

Fixes:

• Trouble with "export async function"? #136
• JSON.parse('-0') should evaluate to -0 #137
• And a lot more, especially for BigInt, thanks to test262...