[Rules] Fix build with WEBSERVER_NEW_RULES

- handle_rules_edit(String, bool) is static now, but ESPEasy_WebServer.cpp
  still called it for /rules/add, which no longer compiles:
  "too many arguments to function 'bool handle_rules_edit(const String&)'"
  Add handle_rules_add() in Rules.cpp and use that instead.
- Rules.cpp uses validIntFromString() without including Numerical.h
  (this was already broken on mega when WEBSERVER_NEW_RULES is defined).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018S3oPMc7qQGQGGGyMUvcaf

src/src/WebServer/ESPEasy_WebServer.cpp

@@ -304,10 +304,7 @@ static void WebServerInit()
   web_server.on(F("/rules"),         handle_rules_new);
   web_server.on(F("/rules/"),        Goto_Rules_Root);
   # ifdef WEBSERVER_NEW_RULES
-  web_server.on(F("/rules/add"),     []()
-  {
-    handle_rules_edit(web_server.uri(), true);
-  });
+  web_server.on(F("/rules/add"),    handle_rules_add);
   web_server.on(F("/rules/backup"), handle_rules_backup);
   web_server.on(F("/rules/delete"), handle_rules_delete);
   # endif // WEBSERVER_NEW_RULES

src/src/WebServer/Rules.cpp

@@ -16,6 +16,7 @@
 
 #include "../Globals/Settings.h"
 #include "../Helpers/ESPEasy_Storage.h"
+#include "../Helpers/Numerical.h"
 #include "../Helpers/StringConverter.h"
 
 #include <FS.h>
@@ -644,6 +645,14 @@ bool handle_rules_edit(const String& originalUri)
   return handle_rules_edit(originalUri, false);
 }
 
+# ifdef WEBSERVER_NEW_RULES
+void handle_rules_add()
+{
+  handle_rules_edit(web_server.uri(), true);
+}
+
+# endif // ifdef WEBSERVER_NEW_RULES
+
 void Goto_Rules_Root() {
   sendHeader(F("Location"), F("/rules"), true);
   web_server.send(302, F("text/plain"), EMPTY_STRING);

src/src/WebServer/Rules.h

@@ -27,6 +27,7 @@ void handle_rules();
 void handle_rules_new();
 
 # ifdef WEBSERVER_NEW_RULES
+void handle_rules_add();
 void handle_rules_backup();
 void handle_rules_delete();
 #endif