add: diffnav, gh-dash, lazygit, k9s overrides

these are all overlays that were part of my nix config before i created
my nur. i am putting them here to reduce build time when building my nix
config

pkgs/default.nix

@@ -8,6 +8,10 @@
   atuinLatest = pkgs.atuinLatest;
   containerLatest = pkgs.containerLatest;
   cliampLatest = pkgs.cliampLatest;
+  lazygitLatest = pkgs.lazygitLatest;
+  ghDashLatest = pkgs.ghDashLatest;
+  diffNavLatest = pkgs.diffNavLatest;
+  k9sLatest = pkgs.k9sLatest;
 
   # any packages that are added to pkgs and are inputs, we inherit them here
   inherit hildibrand;