std.json follows interoperability recommendations from RFC8259 to limit
JSON number values to those that fit inside an f64. However, since Zig
supports arbitrarily large JSON numbers, this breaks roundtrip data
congruence.
To appease both use cases, I've added an option `emit_big_numbers_quoted`
to StringifyOptions. It's disabled by default which preserves roundtrip
but can be enabled to favor interoperability.
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
