feat: return error on build dispatch panic

[tdejager]

We were now getting this ugly error message, on a BuildDispatch failure:

▪ solving              [━━━━━━━━━━━━━━━━━━━━]  1/1
⠒ updating lock-file   [00:00:00] [────────────────────────────────────────]    0/3
  ⠁ default:osx-arm64    [00:00:00] resolving sdist==0.0.0
thread 'main2' panicked at /Users/tdejager/development/prefix/pixi-work/crates/pixi_core/src/lock_file/resolve/build_dispatch.rs:419:14:
  ⠁ default:osx-arm64    [00:00:00] resolving sdist==0.0.0
thread 'main' panicked at src/main.rs:49:10:
Tokio executor failed, was there a panic?: Any { .. }

After this:

▪ solving              [━━━━━━━━━━━━━━━━━━━━]  1/1
⠤ updating lock-file   [00:00:00] [━━━━━━━━━━━━━╾──────────────────────────]    1/3
  ⠁ default:osx-arm64    [00:00:00] resolving sdist==0.0.0
thread 'main2' panicked at /Users/tdejager/development/prefix/pixi/crates/pixi_core/src/lock_file/resolve/build_dispatch.rs:429:17:
  ⠁ default:osx-arm64    [00:00:00] resolving sdist==0.0.0                                                                                                                                                            Error:   × failed to solve the pypi requirements of environment 'default' for platform 'osx-arm64'
  ╰─▶ build dispatch initialization failed: installation of conda environment is required to solve PyPI source dependencies but `--no-install` flag has been set

We still get the panic_handler message, but we would need to replace the default handler and I think thats pretty scary in an async context.

To run

[workspace]
authors = ["Tim de Jager <tdejager89@gmail.com>"]
channels = ["https://prefix.dev/conda-forge"]
name = "sdist"
platforms = ["osx-arm64"]
version = "0.1.0"

[tasks]

[dependencies]
python = ">=3.13.5,<3.14"

# on this branch
pixi add --pypi sdist --no-install

[nichmor]

looks good!