tidy-up: miscellaneous

- INSTALL-CMAKE.md: add missing periods, text fixes.
- md4, md5: sync variables names.
- curl_trc: sync an argument type.
- docs/examples: sync debug/trace function copies, constify, tidy-ups.
- replace commented code with `#if 0`.
- drop redundant parenthesis (macro values, `return`, around single
  variables, function calls).
- fix indentation, apply clang-format in places.

Closes #20481

tests/libtest/cli_upload_pausing.c

@@ -65,7 +65,9 @@ static int progress_callback(void *clientp,
   {
     CURL *curl = (CURL *)clientp;
     curl_easy_pause(curl, CURLPAUSE_CONT);
-    /* curl_easy_pause(curl, CURLPAUSE_RECV_CONT); */
+#if 0
+    curl_easy_pause(curl, CURLPAUSE_RECV_CONT);
+#endif
   }
 #endif
   return 0;