feat: Support hexadecimal floating point literals

[MaxGraey]

Examples

0x1.999999999999ap-4
-0X0.1P4
-0x1A.p+100

Motvation

• Hexadecimal float pointing literals can represent float points exactly without complicated and expensive parsing. It's quite useful for math calculations;
• Hexadecimal float pointing format supported in many languages (C, C++, Julia and etc). Therefore, support for this format makes it easier migration;
• Hexadecimal float pointing format supported by WebAssembly spec. And since we support the same things as WebAssembly, it makes sense to add support to the language itself.

~~As always, the TS language doesn't support such literal format, so as usual we can use the standard way (@ts-ignore) to mute ts checker.~~

Firstly, we need to add built-in literal templates like:

f64`0x1.999999999999ap-4`
i32`123`

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