Add installation and packaging targets

[zhangrongchuan]

Add installation and packaging targets

This PR adds CMake install rules and CPack configuration to generate .tar.gz
and .deb packages for the cpackexample project.

Build & Package

Inside the Docker container:

mkdir build && cd build
cmake ..
make -j
make package

This produces:

• cpackexample-0.1.0-Linux.tar.gz
• cpackexample_0.1.0_amd64.deb

Both archives contain the installed executable, library, and header files.

Debian Package Test

apt install ./cpackexample_0.1.0_amd64.deb
cpackexample

The installed executable runs correctly.

Lintian

lintian was executed as required:

lintian ./cpackexample_0.1.0_amd64.deb > lintian_output.txt

The report is included in the repository.