`tools.build:*flags` documentation is confusing

For example `tools.build:sharedlinkflags` [documentation ](https://docs.conan.io/2.0/reference/config_files/global_conf.html) says

> List of extra flags used by CMakeToolchain for CMAKE_SHARED_LINKER_FLAGS_INIT variable

I think this is not entirely true, because I see that these extra flags are propagated to other generators too

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/microsoft/toolchain.py#L219

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/gnu/autotoolstoolchain.py#L133

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/microsoft/nmaketoolchain.py#L81

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/meson/toolchain.py#L341

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/apple/xcodetoolchain.py#L45

Or `tools.build:cxxflags` documentation says

> List of extra CXX flags used by different toolchains like CMakeToolchain, AutotoolsToolchain and MesonToolchain

and at the same time I see that this configuration is used in `MSBuildToolchain` which is not mentioned

https://github.com/conan-io/conan/blob/6aa9bf6823383610ccf9abe50172eb841832c79d/conan/tools/microsoft/toolchain.py#L217

Probably not a documentation issue, but... I'm trying to build a large dependency tree, and I don't even know what *Toolchain or *Deps they use, and I want some confidence. I would like documentation to say that all my flags are just propagated without mentioning generators. If this isn't the case for some generators, a big fat red error when my linker flags aren't propagated will be a huge plus.

Start with the global_conf documentation linked in the issue and compare its descriptions with the cited toolchain.py locations for Microsoft, GNU, Meson, and Apple generators. Confirm which tools receive each tools.build:*flags setting, then update the documentation to describe the actual propagation and identify any exceptions or missing error behavior.

Written by the indexing model from the issue text.