Bluetooth: testlib: Fix includes (IWYU)

[alwa-nordic]

This commit fixes all includes in testlib according to IWYU rules and sorts all includes in ascending order by name.

[Copilot]

Copilot reviewed 15 out of 15 changed files in this pull request and generated no comments.

[alwa-nordic]

@aescolar

Looks like bsim tests were skipped for this. They probably shouldn't. Do we need to adjust the triggers?

[aescolar]

Looks like bsim tests were skipped for this. They probably shouldn't. Do we need to adjust the triggers?

@alwa-nordic yep. Thanks for pointing it out
#88677

[Thalley]

autoconf.h is a funny include, because of the way it's included. My Clang-tidy finds it under zephyr/autoconf.h after compilation, but it can also be included like this.

I don't have a opinion of whether to use one or the other, but we probably should be somewhat consistent

[alwa-nordic]

Looks like zephyr/autoconf.h is the preferred way.

zephyr/Kconfig.zephyr

Lines 1105 to 1116 in e1a0350

	config LEGACY_GENERATED_INCLUDE_PATH
	bool "Legacy include path for generated headers"
	default y
	help
	Allow applications and libraries to use the Zephyr legacy include
	path for the generated headers which does not use the `zephyr/` prefix.
	From now on, i.e., the preferred way to include the `version.h` header is to
	use <zephyr/version.h>, this Kconfig is currently enabled by default so that
	user applications won't immediately fail to compile.
	This Kconfig will be deprecated and eventually removed in the future releases.

[alwa-nordic]

The -I argument to gcc for include/generated/zephyr is placed before include/generated on the command line in the compilation database. That's probably why my clangd picked that one up.

[alwa-nordic]

Fixed the autoconf includes.