🐛 Fix shared-library builds and packaging

[burgholzer]

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Description

Fix the BUILD_SHARED_LIBS=ON configuration failure noted in #2352, now merged into main.

• Keep private compiler libraries and bundled jeff dependencies static. Public Core libraries still honor the shared-build option; the QDMI device no longer requires unexported compiler shared libraries.
• Remove the global install-RPATH override so shared libraries can find their dependencies before installation.
• Place the shared QDMI driver beside the device manifests it discovers.
• Add a debug-shared preset and use it in the existing Linux Debug CI job. Document the linkage policy.

Validation on Linux ARM64 with LLVM/MLIR 23.1.0:

• Shared Debug and static Release builds: 3,812 tests passed and one expected skip each.
• Installed the Core Runtime/Development and QDMI Development components, relocated the prefix, then configured, built, and ran a separate find_package(mqt-core) consumer. It discovered and loaded DDSIM without compiler targets or private compiler shared libraries.
• uvx nox -s lint and git diff --check passed. No C++ sources changed.

Codex assisted with implementation, validation, and this description. No standalone changelog entry is added for this unreleased compiler infrastructure fix.

Checklist

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[burgholzer]

Closing this one. We do not build with BUILD_SHARED_LIBS enabled for a reason.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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