Remove nvim.desktop in favor of symlink

Moving to symlink fixes the following issues:
- App removes from launchers if you uninstall Nvim
- Nvim launches in the correct terminal without invalid desktop entry

Symlink setup moved to omarchy-nvim-setup (Ref:
https://github.com/omacom-io/omarchy-pkgs/commit/bb7a0f4c1f78d428bbe53bc3af2c91a9c8a5de3b)

applications/nvim.desktop

@@ -1,12 +0,0 @@
-[Desktop Entry]
-Name=Neovim
-GenericName=Text Editor
-Comment=Edit text files
-Exec=$TERMINAL -e nvim %F
-Terminal=false
-Type=Application
-Keywords=Text;editor;
-Icon=nvim
-Categories=Utility;TextEditor;
-StartupNotify=false
-MimeType=text/english;text/plain;text/x-makefile;text/x-c++hdr;text/x-c++src;text/x-chdr;text/x-csrc;text/x-java;text/x-moc;text/x-pascal;text/x-tcl;text/x-tex;application/x-shellscript;text/x-c;text/x-c++;