cmake build system refactor

[freemine]

Description

#29455

this PR is based on the early TDengine commit (acdee96), thus can't be merged automatically. but it does NOT matter as far as what this PR is about to demonstrate.

how to build with it:

• Linux/MacOSX

cmake -B debug -DWEBSOCKET=true -DBUILD_TOOLS=true -DBUILD_CONTRIB=true -DBUILD_HTTP=false -DBUILD_KEEPER=true -DBUILD_TEST:BOOL=ON
cmake --build debug -j4

• Windows

cmake -B build -DBUILD_CONTRIB:BOOL=ON -A x64
cmake --build build -j4

hints:

check with first several lines in ./CMakeLists.txt

Checklist

Please check the items in the checklist if applicable.

• Is the user manual updated?
• Are the test cases passed and automated?
• Is there no significant decrease in test coverage?

[freemine]

currently, build/install/test processes are all passed on linux/macosx.
but on windows, taosd and related stuffs do NOT compile, and neither install/test processes has been tested locally.
if you wanna check if taos.exe has compiled successfully, check with this:

.\build\build\bin\Debug\taos.exe -E taosws://host:6041/path-to-server