fix: enable 'boot.tmp.useTmpfs' based on host 'highRam' flag

hosts/andromache/host.nix

@@ -2,5 +2,6 @@
   host = {
     username = "h";
     name = "andromache";
+    highRam = true;
   };
 }

hosts/astyanax/host.nix

@@ -2,5 +2,6 @@
   host = {
     username = "h";
     name = "astyanax";
+    highRam = true;
   };
 }

modules/boot/bootloader.nix

@@ -1,4 +1,11 @@
+{ config, ... }:
+
 {
-  boot.loader.systemd-boot.enable = true;
-  boot.loader.efi.canTouchEfiVariables = true;
+  boot = {
+    loader = {
+      systemd-boot.enable = true;
+      efi.canTouchEfiVariables = true;
+    };
+    tmp.useTmpfs = config.host.highRam;
+  };
 }

modules/common/host.nix

@@ -19,5 +19,10 @@
       type = lib.types.str;
       default = "en_US.UTF-8";
     };
+
+    highRam = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+    };
   };
 }