networks: fix ordering and add new network

nix/networks/list.nix

@@ -81,6 +81,13 @@ in
     hasPassword = true;
     randomizeMac = true;
   }
+  {
+    ssid = "LouisaCoffee";
+    bssid = "fa:92:bf:62:7c:19";
+    priority = privatePriority;
+    hasPassword = true;
+    randomizeMac = true;
+  }
   {
     ssid = "MetroTaipei x Louisa"; # 大安
     priority = privatePriority;

nix/networks/wpa_supplicant-compat.nix

@@ -20,12 +20,13 @@ let
       randomizeMac ? false,
       ...
     }:
-    let
-      uniqueKey = "${ssid}${lib.optionalString (bssid != null) bssid}";
-    in
     {
-      ${uniqueKey} # we use a unique key here to make sure no "same ssid different bssid" networks collide in key.
-        =
+      ${
+        # We use a unique key here to make sure no "same ssid different bssid" networks collide in key.
+        # This is ordered, we still show "null" so that it would come after hex characters [a-z0-9].
+        # The serialization is based on string order.
+        "${ssid},${if bssid != null then bssid else "null"}"
+      } =
         lib.mkMerge [
           (builtins.removeAttrs networkArgs [
             "hasPassword"
@@ -33,7 +34,10 @@ let
             "randomizeMac"
           ])
           (lib.optionalAttrs hasPassword {
-              pskRaw = "ext:${escapePwdKey uniqueKey}"; # this implies changing the external password key if you set a bssid!
+            pskRaw = "ext:${
+              # this implies changing the external password key if you set a bssid!
+              escapePwdKey (if bssid == null then ssid else "${ssid},${bssid}")
+            }";
           })
           {
             extraConfig = ''