renamed prog to begin and added basics for the manual

src/visualization.cpp

@@ -1,4 +1,19 @@
 proc visualize_lisp_machine() -> void {
+
+    // save the current working directory
+    char cwd[1024];
+    getcwd(cwd, 1024);
+    // get the direction of the exe
+    char* exe_path = exe_dir();
+    // switch to the exe directory for loading pre.slime
+    chdir(exe_path);
+    free(exe_path);
+
+    defer {
+        // switch back to the users directory
+        chdir(cwd);
+    };
+
     struct Drawn_Area {
         int x;
         int y;