chore: remove QuickNav addon from build and loader (#343)

- Remove QuickNav install block from src/Mod/Create/CMakeLists.txt
- Remove mods/quicknav submodule entry from .gitmodules
- Remove quicknav imports and TestWorkbenchMap tests from test_kindred_pure.py
- Remove mods/quicknav submodule from git tracking

QuickNav will be archived to a reference folder in a separate step (#345).
This is part of the UI/UX rework epic (#346).

.gitmodules

@@ -22,6 +22,3 @@
 	path = mods/solver
 	url = https://git.kindred-systems.com/kindred/solver.git
 	branch = main
-[submodule "mods/quicknav"]
-	path = mods/quicknav
-	url = https://git.kindred-systems.com/kindred/quicknav.git