[cmake] Configuration issue due to `spdlog` and export sets

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Describe the bug

Cmake configuration fails at the end with:

-- Configuring done (14.9s)
CMake Error: install(EXPORT "cudaq-common-targets" ...) includes target "cudaq-common" which requires target "spdlog" that is not in any export set.
-- Generating done (0.2s)
CMake Generate step failed.  Build files cannot be regenerated correctly.

Steps to reproduce the bug

Run CMake configuration:

• Use a preset file (see attached CMakeUserPresets.json). All paths are examples, please use relevant paths on your system. You can also simply use command line options directly.
• run cmake --preset debug

The config step with right at the end with:

CMakeUserPresets.json

-- Configuring done (14.9s)
CMake Error: install(EXPORT "cudaq-common-targets" ...) includes target "cudaq-common" which requires target "spdlog" that is not in any export set.
-- Generating done (0.2s)
CMake Generate step failed.  Build files cannot be regenerated correctly.

Expected behavior

Cmake configuration and build are expected to run normally with no blockers (under reasonable local tweaks)

Is this a regression? If it is, put the last known working version (or commit) here.

Not a regression

Environment

• CUDA-Q version: 12.8.93
• Python version: 3.13
• C++ compiler: Clang 19
• Operating system: Arch Linux

Suggestions

No response

Start with CMakeUserPresets.json and reproduce the failure using cmake --preset debug. Trace the cudaq-common-targets export configuration and its dependency on spdlog; done means CMake configuration and generation complete without the reported export-set error.