Tier System: `x86_64-haiku`

[vazub]

Would be great to add proper support for this OS - https://www.haiku-os.org/

Headers: https://github.com/haiku/haiku/tree/master/headers

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The current goal is Tier 3. Once Zig reaches Tier 3 this issue will get renamed to Tier 2, and so on.

[vazub]

There appears to be WIP for this in #7546

[ypsvlq]

tips for anyone looking into this currently:

• run nightly (new malloc is needed)
• ~~build your own LLVM -- checkout haikuports and remove this line and this patch~~ no longer needed for LLVM20, fixed in haikuports

[The-King-of-Toasters]

State of affairs after the std.Io merge:

• libroot doesn't expose preadv/pwritev, but has the equivalent readv_pos/writev_pos. See #25739.
• SIGIO is not available so some other signal needs to be used.