Shellcode for fish

[mxcl]

Refs #704

[coveralls]

Pull Request Test Coverage Report for Build 6667484083

• 15 of 27 (55.56%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.7%) to 96.222%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/modes/shellcode.ts	15	27	55.56%
<!--	Total:	15	27

Totals
Change from base Build 6653611079:	-0.7%
Covered Lines:	1392
Relevant Lines:	1441

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💛 - Coveralls

[FlatMapIO]

@mxcl Don't forget this :)

[yoroshikun]

Very eager for this~

[joshmedeski]

@mxcl let us know if you need any testers for this! Looking forward to seeing this merged.

[mxcl]

I think I need to refactor the shellcode and other related pieces before this will be maintainable. I don't use fish (only because in general I stick with defaults so that I know what most of my users deal with on a day to day basis) and as a result it would be easy for it to end up breaking unless the underlying infra is solid.

Also not knowing fish it's hard to write. I am mostly using ChatGPT to translate.

[netzhuffle]

@mxcl Do you have anything in specific about how I might be able to help?

[joshmedeski]

@mxcl I've got fish scripting experience too, let us know if you want support.

[amok]

I'm at your service too, @mxcl. Looking forward to fish support

[aybabtme]

This would help contributing to the pantry, as it relies on integration https://github.com/pkgxdev/pantry?tab=readme-ov-file#contributing