* Use PROJECT_SOURCE_DIR rather than CMAKE_SOURCE_DIR to allow building as subdirectory
* Also use PROJECT_SOURCE_DIR instead of CMAKE_SOURCE_DIR in c/cxx api examples
* Only build examples by default when not building as subdirectory
* Do not suggest building binaries either
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Co-authored-by: user <user@mail.tld>
When `-D BUILD_SHARED_LIBS=ON` is passed to `cmake`, it builds a single shared library.
Specifically,
- For C APIs, it builds `libsherpa-onnx-c-api.so`
- For Python APIs, it builds `_sherpa_onnx.cpython-xx-xx.so`
- For Kotlin and Java APIs, it builds `libsherpa-onnx-jni.so`
There is no `libsherpa-onnx-core.so` any longer.
Note it affects only shared libraries.
