Set SOVERSION 1 for Apple builds to match Linux library versioning (#28101)
### Description
Include Apple in the existing `SOVERSION 1` block by changing the CMake
condition from `if(NOT APPLE AND NOT WIN32)` to `if(NOT WIN32)`.
**Before:** macOS install name is `@rpath/libonnxruntime.1.20.0.dylib` —
dependents pinned to exact version.
**After:** macOS install name is `@rpath/libonnxruntime.1.dylib` —
dependents only require major version, matching Linux
`libonnxruntime.so.1`.
The actual library file remains `libonnxruntime.<VERSION>.dylib`, so
existing packaging scripts (`copy_strip_binary.sh`,
`mac-cpu-packaging-steps.yml`, `js/node/CMakeLists.txt`) are unaffected.
CMake creates the intermediate `libonnxruntime.1.dylib` symlink
automatically.
### Motivation and Context
On macOS, linking against onnxruntime embeds the full-versioned install
name, causing `dlopen` failures when a different patch version is
installed:
```
dlopen(dependent.dylib, 0x0001): Library not loaded: @rpath/libonnxruntime.1.20.0.dylib
```
Linux already avoids this via `SOVERSION 1`. The exclusion of Apple from
that code path appears unintentional.
---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: tianleiwu <30328909+tianleiwu@users.noreply.github.com>