feat(nginx): add extraLocations option for WebSocket support

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

modules/nginx.nix

@@ -44,6 +44,23 @@ in
             default = "";
             description = "Extra Nginx config for this location";
           };
+          extraLocations = lib.mkOption {
+            type = lib.types.attrsOf (lib.types.submodule {
+              options = {
+                proxyPass = lib.mkOption {
+                  type = lib.types.str;
+                  description = "Proxy target URL";
+                };
+                extraConfig = lib.mkOption {
+                  type = lib.types.lines;
+                  default = "";
+                  description = "Extra Nginx config for this location";
+                };
+              };
+            });
+            default = { };
+            description = "Additional location blocks to add to this virtual host";
+          };
         };
       });
       default = { };
@@ -79,10 +96,18 @@ in
           enableACME = true;
           forceSSL = true;
 
-          locations."/" = {
+          locations = {
+            "/" = {
               proxyPass = "http://127.0.0.1:${toString opts.port}";
               extraConfig = opts.extraConfig;
             };
+          } // lib.mapAttrs' (locPath: locOpts: {
+            name = locPath;
+            value = {
+              proxyPass = locOpts.proxyPass;
+              extraConfig = locOpts.extraConfig;
+            };
+          }) opts.extraLocations;
         };
       }) cfg.domains;
     };