pkg(highway): Enable system-integration

[AnthonyZhOon]

Move bridge.cpp to being a module cSourceFile instead of part of the staticlib Dynamic link against highway with pkg-config name 'libhwy.pc' when system-integrated

Some concerns:

• Running ldd zig-out/bin/ghostty after building with zig build -Doptimize=ReleaseFast does not show libhwy.so but is included in debug optimize.

  • The staticlib variant also compiles without source files in release mode but not in debug due to missing symbols hwy::Abort().
  • Would look into how highway works more to understand this, it looks to extensively use templates and template-specialisations which results in little shared object code?

• We configure a few optimization related flags (vectorization, constants), ran a quick DOOM-fire and cats and it seems okay

• There's a few macro defines for predefined macros (DATE, TIMESTAMP, TIME) that are overrided in the static lib. The comment seems to imply that they are for reproducible binaries so I think it shouldn't change runtime behaviour.

[AnthonyZhOon]

Checking highway's source, it simply appears that much of the implementation is in the header files and template instantiations. It should be fine that libhwy.so is entirely cleaned out by link-time optimizations.

[mitchellh]

Please rebase for all the latest build changes, shouldn't be much work. Thank you!

[AnthonyZhOon]

I chose to add an import module in the SharedDeps.zig similar to how other libs that expose a zig module over C files now that bridge.cpp is not compiled into the static lib.
Although it seems the extern "c" fn hwy_supported_targets() i64 is not used in ghostty

[mitchellh]

I'm going to merge this for now and I defaulted the system integration to true (for packaging). I am suspicious that this will work in practice because I've found each highway version changes the API in ways that its usually pretty tied but we'll see!

[mitchellh]

I'm not at the computer but we need to add highway as a package to our Debian 12 test.

[AnthonyZhOon]

Updated the Debian 12 build env

[mitchellh]

Okay yeah, this is what I expected. The dependency on Debian 12 is too old and the API isn't stable. I'm going to default the system integration to false and packagers who really care can enable it.

[AnthonyZhOon]

Merged the Nix conflicts and built successfully with it

[mitchellh]

I think the merge with main was incorrect, it undoes some changes around the Nix files. I can take a look later but can't merge until then.

[hqnna]

Please rebase your branch so it includes the po/nb_NO.UTF-8.po file, thanks.

[AnthonyZhOon]

I've taken the patch of the package changes and applied it onto main but left out the nix/ changes @mitchellh made

[hqnna]

The changes look much cleaner now, and don't effect irrelevant files.

[AnthonyZhOon]

Looking at the nix config, I've added libhwy to the devshell but not to the package.nix as we've decided not to have highway as a default system integration with zig build --system since glslang and spirv-cross integration are similarly not in the nix package.