Can't convert BigInt to Decimal without throwing an error

[James103]

Currently (latest break_infinity.js version as of 2023-01-11), attempting to convert a BigInt value to Decimal will throw an error with the following message from within the toString function: TypeError: t.indexOf is not a function (where t is the input argument).

For example, new Decimal(1000n) should return a Decimal representing the number 1000 but currently throws an error.
new Decimal(2n**1234n) should return a Decimal whose value is approximately 2.958112e371 but also throws an error.

A similar issue exists for break_eternity.js: Patashu/break_eternity.js#142