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

src/tool_ipfs.c

@@ -33,7 +33,7 @@
 static bool has_trailing_slash(const char *input)
 {
   size_t len = strlen(input);
-  return (len && input[len - 1] == '/');
+  return len && input[len - 1] == '/';
 }
 
 static char *ipfs_gateway(void)