[MIRROR] Remove Uncross() and CheckExit(), add connect_loc element to cover the cases we used it for (#4756)

* Remove Uncross() and CheckExit(), add connect_loc element to cover the cases we used it for (#58188)

* Remove Uncross(), add create_loc element

* Update on ChangeTurf

* Explicit return

* Hold onto elements and remove TEST_FOCUS

* Remove UNIT_TESTS compile flag

* Follow my own advice.

* Comment about Uncross + CRASH

* Remove /atom/Exit ..()

* Apply suggestions from code review

Co-authored-by: Emmett Gaines <ninjanomnom@gmail.com>

* Use keyed locs

* Re-add Bump()

* Superfluous check

* Correct change turf signal, remove old continue check

* Fix compile failure

* Fix tests

* Don't create element for fulltile windows

* Correctly unregister old location

Co-authored-by: Emmett Gaines <ninjanomnom@gmail.com>

* Fixed (?)

Co-authored-by: Mothblocks <35135081+Mothblocks@users.noreply.github.com>
Co-authored-by: Emmett Gaines <ninjanomnom@gmail.com>
Co-authored-by: Useroth <37159550+Useroth@users.noreply.github.com>

code/modules/unit_tests/_unit_tests.dm

@@ -48,6 +48,7 @@
 #include "chain_pull_through_space.dm"
 #include "combat.dm"
 #include "component_tests.dm"
+#include "connect_loc.dm"
 #include "confusion.dm"
 #include "crayons.dm"
 #include "designs.dm"