cmake: Install shared libs

[phodina]

Purpose

Install depthai shared libraries and other build artifacts into the system using CMake

Also sets correctly the RPATH otherwise it would point to the build dir.

Testing & Validation

Tested on Linux and MacOSX

[phodina]

Set and propagate RPATH settings across targets and Python components

• Ensured BUILD_WITH_INSTALL_RPATH is enabled for correct runtime linking.
• Added proper RPATH handling to Python bindings and test modules for macOS and Linux to ensure correct runtime library resolution.

[phodina]

@moratom so removed the code regarding the dependencies which is no longer needed. But rest is needed for system install and correct RPATH

[phodina]

@SzabolcsGergely could I ask you for review?