Add workflow to test CMake builds against installed sc, p4est, and ThunderEgg

[Copilot]

Adds CI workflow to verify forestclaw builds correctly against pre-installed sc, p4est, and ThunderEgg dependencies from submodules, rather than using them as subdirectories.

Changes

• New workflow .github/workflows/ci_cmake_installed.yml that:
  • Builds and installs sc from submodule with configurable MPI support
  • Builds and installs p4est from submodule using installed sc (P4EST_USE_SYSTEM_SC=ON)
  • Builds and installs ThunderEgg from submodule with MPI and FFTW support (conditionally when enabled)
  • Builds forestclaw with FCLAW_ENABLE_SUBMODULES=OFF to consume installed libraries
• Tests 5 Linux configurations (serial/MPI, with/without clawpack, with ThunderEgg)
• Tests macOS-27 builds with clawpack, geoclaw, and thunderegg enabled
• Includes explicit permissions: contents: read for security

Build flow

# sc build propagates MPI config from matrix
cmake -B build -DSC_ENABLE_MPI=${{ contains(matrix.configure_flags, '-Dmpi=ON') && 'ON' || 'OFF' }}

# p4est uses installed sc
cmake -B build -DP4EST_USE_SYSTEM_SC=ON -Dmpi=...

# thunderegg (conditionally built when -Dthunderegg=ON)
cmake -B build -Dmpi=ON -Dfftw=ON -Dp4est=OFF

# forestclaw discovers installed dependencies via CMAKE_PREFIX_PATH
cmake --preset ci -Dsubmodules=OFF ${{ matrix.configure_flags }}

This validates the install/find_package workflow for packaging scenarios.

Created from VS Code via the GitHub Pull Request extension.

Created from VS Code via the GitHub Pull Request extension.

Original prompt

add a github workflow that test a CMake build with an installed version of sc and p4est. It should use the sc and p4est submodule.

Created from VS Code via the GitHub Pull Request extension.

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[scottaiton]

@copilot It should test an installed version of thunderegg also

[Copilot]

@copilot It should test an installed version of thunderegg also

Added ThunderEgg support to the workflow. The workflow now:

• Builds and installs ThunderEgg from the submodule (with MPI and FFTW)
• Includes a new "MPI With ThunderEgg" test configuration on Linux
• Enables ThunderEgg on macOS builds

Changes in commit 3a9badc.

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:

• esm.ubuntu.com
  • Triggering command: /usr/lib/apt/methods/https (dns 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)

[scottaiton]

@copilot change the macos job to run on macos 27

[Copilot]

@copilot change the macos job to run on macos 27

Changed the macOS job to run on macos-27.

Changes in commit 8fae745.