retain exported NSRunningApplication reference to avoid autorelease

[donaldguy]

(X-fork clone of koekeishiya#973):

Per discussion/thinking outloud in koekeishiya#967 (koekeishiya#967 (comment) ) with nod from @koekeishiya – Added explicit call to retain before returning to C++:

https://developer.apple.com/documentation/objectivec/1418956-nsobject/1571946-retain

this seems to be a better way to fix koekeishiya#920 and possibly other crashes in Monterey (and who knows, maybe even earlier); and probably should have been in 8c9bbbe in the first place

I built this (on xorpse/master) and can open and close application without any crash so far on Monterey beta 3 (21A5294g) *knock on wood*

(neither the immediate crashes I was seeing on application launch before, nor the GC-triggered crash as in koekeishiya#923 (comment) )

---

If this were not needed it would probably introduce a memory leak.

To check I set an lldb breakpoint at https://github.com/koekeishiya/yabai/blob/8777db43b8551e0bc4e5c55d1e15bcbed52501a1/src/workspace.m#L60

Once triggered, I found that:

(lldb) p [application retainCount]
(unsigned long long) $3 = 1

and

(lldb) p (NSObject*)[ application release]
(NSObject *) $5 = nil
(lldb) p (NSObject*)[ application release]
error: Execution was interrupted, reason: EXC_BREAKPOINT (code=1, subcode=0x18d284930).
The process has been returned to the state before expression evaluation.

so seems good to me

[donaldguy]

further exploration: koekeishiya#973 (comment)

suggests this works on both Monterey / arm64e (where it eliminates several crashes) and Big Sur / x86_64 but may leak memory on the latter ;

there is likely a set of annotations (amongst those mentioned somewhere on https://clang.llvm.org/docs/AutomaticReferenceCounting.html ) that would create consistent behavior on the two versions/platforms, but I'm not quite sure what they are (nor what has changed/is changing in clang 13 to require this call where it previously was not needed - though I suspect it may relate to a tweak in how the word create in a method name is or is not considered special)