Add nix config and reduce sway gaps

dot_config/fish/executable_config.fish

@@ -11,6 +11,11 @@ if test -z "$XDG_RUNTIME_DIR"
   end
 end
 
+# Set Nix include path if it exists
+if test -e ~/.nix-profile/etc/profile.d/nix.sh
+  fenv source ~/.nix-profile/etc/profile.d/nix.sh
+end
+
 # PATH adjustment
 setpath ~/.rbenv/shims
 setpath ~/.rbenv/bin

dot_config/fish/executable_fishfile

@@ -1,2 +1,3 @@
 jethrokuan/z
 jorgebucaran/fish-nvm
+oh-my-fish/plugin-foreign-env