caddy: make each machine have a seperate subdomain based on their hostname

zsh-syntax-highlighting may not highlight the text currently in the
prompt, sometimes making text look as if zsh-syntax-highlighting wasn't
there at all. before this the colour was black which made it unreadable.

modules/services/caddy.nix

@@ -8,7 +8,7 @@
   };
 
   config = {
-    homelab.domain = "int.astolfo.org";
+    homelab.domain = "${config.networking.hostName}.astolfo.org";
     networking.firewall.allowedTCPPorts = [ 80 443 ];
     
     services.caddy = {

stow/.zshrc

@@ -48,7 +48,7 @@ else
   TEXT_COLOUR="{black}"
 fi
 
-PROMPT="%K$PRIMARY_COLOUR%F$TEXT_COLOUR %~ %K$SECONDARY_COLOUR $OSICON %k "
+PROMPT="%K$PRIMARY_COLOUR%F$TEXT_COLOUR %~ %K$SECONDARY_COLOUR $OSICON %k%F{white} "
 RPROMPT="%F{7}$HOSTNAME"
 
 bindkey -e