[Backport into 5.15] Removing unique and the unused NAN_SET_BUF_DETACH

[shirady]

Explain the changes

1. unique was removed from shared_ptr
   This PR removes unique and the unused NAN_SET_BUF_DETACH

Signed-off-by: liranmauda [email protected]
(cherry picked from commit 0215f39)

More details in the original PR: #8513

Issues:

1. After updating Mac OS M1 we started to face the error (on npm run rebuild):

In file included from ../src/native/fs/fs_napi.cpp:3:
../src/native/fs/../util/buf.h:173:23: error: no member named 'unique' in 'std::shared_ptrnoobaa::Buf::Alloc'
173 | return _alloc.unique();
| ~~~~~~ ^
1 error generated.
make: *** [Release/obj.target/nb_native/src/native/fs/fs_napi.o] Error 1
gyp ERR! build error
gyp ERR! stack Error: make failed with exit code: 2
gyp ERR! stack at ChildProcess. (/Users/shiradymnik/SourceCode/noobaa-core/node_modules/node-gyp/lib/build.js:216:23)
gyp ERR! System Darwin 24.0.0
gyp ERR! command "/Users/shiradymnik/.nvm/versions/node/v20.11.0/bin/node" "/Users/shiradymnik/SourceCode/noobaa-core/node_modules/.bin/node-gyp" "build"
gyp ERR! cwd /Users/shiradymnik/SourceCode/noobaa-core
gyp ERR! node -v v20.11.0
gyp ERR! node-gyp -v v10.2.0
gyp ERR! not ok

Testing Instructions:

1. I run: npm run rebuild.

Note: original instruction -

see that we can compile using c++20

• Doc added/updated
• Tests added