[PROJ] PROJ should find unofficial-sqlite3 instead of SQlite3 for better multiconfig support

[dbs4261]

Is your feature request related to a problem? Please describe.

I am working on a super build for a project that depends on PROJ. I've been struggling to debug a LNK4098 warning reporting that my application, which I am building in release mode, is linking with something that was built in debug mode. I have eventually tracked this issue down to PROJ. When running CMake with CMAKE_FIND_DEBUG_MODE, I realized that when PROJ is installed with VCPKG the resulting proj-config.cmake script calls find_dependency(SQLite3), this then gets picked up by cmake-3.29/Modules/FindSQLite3.cmake. That's a problem because the default FindSQLite3 module searches with a find_library command and the debug and release versions of the library share the same name.

Proposed solution

A patch should be added to change the find_package call of SQLite3 to unofficial-sqlite3 and update the corresponding imported targets.

Describe alternatives you've considered

Another option would be to set CMAKE_FIND_PACKAGE_PREFER_CONFIG, but this can't be done on a package by package basis.

Additional context

No response

[dg0yt]

I removed the usage of unofficial-sqlite3 in #37650 because I believed the multi-config usage was covered by SQLite::SQLite3. I can confirm now that this is not the case. The best fix would be fixed by a vcpkg cmake wrapper for SQLite3. But as an immediate fix to this issue, #41566 now restores the workaround in port proj.