[GM Commands] Split GM Commands Into Separate Files (#1766)

* Split GM commands into their own files

* Code cleanup

zone/gm_commands/checklos.cpp

@@ -0,0 +1,20 @@
+#include "../client.h"
+
+void command_checklos(Client *c, const Seperator *sep)
+{
+	if (!c->GetTarget()) {
+		c->Message(Chat::White, "You must have a target to use this command.");
+	}
+
+	bool has_los = c->CheckLosFN(c->GetTarget());
+	c->Message(
+		Chat::White,
+		fmt::format(
+			"You {}have line of sight to {} ({}).",
+			has_los ? "" : "do not ",
+			c->GetTarget()->GetCleanName(),
+			c->GetTarget()->GetID()
+		).c_str()
+	);
+}
+