tidy-up: miscellaneous

- tool_bname: scope an include.
- `endif` comments.
- Markdown fixes.
- comment tidy-ups.
- whitespace, newlines, indent.

Closes #20309

src/tool_cb_wrt.c

@@ -231,7 +231,7 @@ static size_t win_console(intptr_t fhnd, struct OutStruct *outs,
   *retp = bytes;
   return 0;
 }
-#endif
+#endif /* _WIN32 */
 
 /*
 ** callback for CURLOPT_WRITEFUNCTION
@@ -303,7 +303,7 @@ size_t tool_write_cb(char *buffer, size_t sz, size_t nmemb, void *userdata)
       return CURL_WRITEFUNC_ERROR;
     }
   }
-#endif
+#endif /* DEBUGBUILD */
 
   if(!outs->stream && !tool_create_output_file(outs, per->config))
     return CURL_WRITEFUNC_ERROR;