62 build times are too high for test saturate

[albertandaluz]

reducing build times by distributing template compilation across separate compilation units
This PR distributes template compilation across separate compilation units to reduce build times for test saturation. The refactoring splits monolithic header-only test files into generated per-type templates that can be compiled in parallel.

Introduces template-based code generation for test compilation units using CMake configure_file
Replaces header-only implementations with shared library builds for better parallelization
Adds build system support for Windows export headers and cross-platform compiler warning suppression
Reviewed Changes

[Copilot]

Pull Request Overview

This PR refactors the test build system to reduce compilation times by distributing template-heavy test code across separate compilation units that can be built in parallel. The changes split monolithic header-only test files into generated per-type templates using CMake's configure_file mechanism.

• Introduces template-based code generation for individual fundamental types (char, int, float, etc.)
• Replaces header-only test implementations with shared library builds for better parallelization
• Adds comprehensive build system support including Windows export headers and cross-platform compiler warnings

Reviewed Changes

Copilot reviewed 23 out of 23 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
utests/core/utils/utest_cuda_vector_utils/*.in	Template files for generating per-type test compilation units
utests/algorithm/image_processing/utest_saturate/*.in	Template files for saturate test per-type compilation units
cmake/tests/*.cmake	Build system support for shared test libraries and export headers
utests/CMakeLists.txt	Updated to use new shared library test approach
CMakeLists.txt	Added export header support and test build options

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[morousg]

I reinstalled VS2022 Community, version 17.14.13, installed CUDA 12.9, using cmake 3.31.5, and I keep getting this project folder structure. I understand that we should see a folder tests and another folder utests, without the FKL "pre-folder".

Maybe it is related to the way the project was cloned? I cloned the repo with source tree, into a folder named FKL.

Please, try to reproduce the issue and fix it. In the mean time, I'm going to chage a few things in how the code is distributed.