Fixed some crashes in response strings source generator, reorganized more submodules into their folders

src/NadekoBot/Modules/Searches/_Common/Exceptions/StreamNotFoundException.cs

@@ -0,0 +1,19 @@
+#nullable disable
+namespace NadekoBot.Modules.Searches.Common.Exceptions;
+
+public class StreamNotFoundException : Exception
+{
+    public StreamNotFoundException()
+    {
+    }
+
+    public StreamNotFoundException(string message)
+        : base(message)
+    {
+    }
+
+    public StreamNotFoundException(string message, Exception innerException)
+        : base(message, innerException)
+    {
+    }
+}