Improve builtin includes

[waruqi]

Is your feature request related to a problem? Please describe.

.

Describe the solution you'd like

Add @builtin/ to find builtin includes.

includes("@builtin/check")

it will be instead of

includes("check_cflags.lua")
includes("check_cfuncs.lua")

We can also use

includes("@builtin/check/check_cflags.lua")

Describe alternatives you've considered

No response

Additional context

No response