Fix Windows wheel builds using pre-built OpenBLAS binaries

[Copilot]

Windows wheel builds were failing due to missing OpenBLAS library during linking.

Changes

• Replaced vcpkg with pre-built OpenBLAS binaries (v0.3.26)

  • Downloads from GitHub releases during before-build
  • Extracts to C:\openblas
  • Eliminates vcpkg complexity and caching issues

• Added delvewheel for DLL bundling

  • Repairs wheels to include OpenBLAS DLLs
  • Makes wheels self-contained and redistributable

• Configuration in pyproject.toml

  [tool.cibuildwheel.windows]
  before-build = [
      "curl -L https://github.com/OpenMathLib/OpenBLAS/releases/download/v0.3.26/OpenBLAS-0.3.26-x64.zip -o openblas.zip",
      "powershell Expand-Archive openblas.zip -DestinationPath C:\\openblas -Force"
  ]
  repair-wheel-command = "pip install delvewheel && delvewheel repair --add-path C:\\openblas\\bin -w {dest_dir} {wheel}"
  
  [tool.cibuildwheel.windows.environment]
  EASYSBA_LAPACK_LIBS = "libopenblas"
  EASYSBA_INCLUDE_DIRS = "C:\\openblas\\include"
  EASYSBA_LIBRARY_DIRS = "C:\\openblas\\lib"

• Removed vcpkg cache step from workflow (no longer needed)

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/repos/OpenMathLib/OpenBLAS/contents/.github/workflows
  • Triggering command: /usr/bin/curl curl -s REDACTED (http block)
• https://api.github.com/repos/OpenPTV/easySBA-python/actions/runs/22159876506/jobs
  • Triggering command: /usr/bin/curl curl -s -H Accept: application/vnd.github+json REDACTED (http block)
• https://api.github.com/repos/OpenPTV/easySBA-python/actions/runs/22160120971
  • Triggering command: /usr/bin/curl curl -s REDACTED (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.