[Feature Request]Add support for android AVD

[androidacy-user]

There is of course the script in scripts/emulator.sh but that is rather tedious to have to execute on each boot, and renders testing modules kinda worthless since they aren't going to be mounted properly, nor boot scripts ran.
As of this moment, checking on a sdk29 official AVD from Android studio, there is a ramdisk.img that could be theoretically patched, if Manager actually supported the format. I tried using commands taken from boot_patch.sh, but it gets stuck at [loading ramdisk.cpio] (which does exist in the directory magiskboot is ran from).
I'd like to see either
A) Manager supports patching (of course not flashing, you'd have to copy the ramdisk back into place yourself) ramdisk.img natively
B) Some sort of documentation on how we can get a (mostly if not fully) working environment in the official AVD.

I'm only suggesting the official AVD from google because there are any combination of other emulators that may or may not have a ramdisk or weird hacks to get things working (not to mention android x86 doesn't want to launch the gui for me), but the AVD will always have a universal setup for each release, and would be very useful for me as a module developer because I wouldn't have to either buy a second device for testing or test on my daily driver. It could also be useful if you want to test out certain mods on a device that is easily disposable or your not sure if it's 100% safe.

[ytrezq]

Aik tools supports android boot image with avd key changing.

[ghost]

@linuxandria try to see this issue #2551, shakalaca has developed a script for patch AVD and android x86, for me the patch for android x86 is working, so I think also AVD is good.

[androidacy-user]

@ematrix would be nice to be able to provide manager with the necessary files and automatically do the needful patches. Or emulator.sh fixed to better support it

[androidacy-user]

• @etmatrix
  GitHub app doesn't let you edit comments lol

[NULL0B]

@linuxandria it's funny I posted similar issue here https://github.com/topjohnwu/Magisk/issues/2471
and you closed it. Patching ramdisk with that method work on android 8.1 AVD but with a very old magisk (16.6 ) other build after that. doesn't boot. I tried canary and it boots put doesn't perform additional install.

[vvb2060]

build.py emulator

[yujincheng08]

20ef724