tidy-up: miscellaneous

- examples: sync debug output printf masks.
- INSTALL-CMAKE.md: tidy up section for some options.
- curl_sha512_256: delete comment suggesting an optimization.
- vtls/keylog: scope a variable.
- vtls/openssl: make a source code URL a permalink.
- vtls/schannel: drop redundant parentheses.
- test1119.pl: robustify `$1` -> `$s`.
- sync arg names in comments to match the code.
- tidy up and minor fixes to comments.
- fix formatting/indenting/comment/newline/include nits.
- move `UNITTEST` protos next to definitions, sync their argument names.
- make variables static.
- add parentheses to Perl `open()` calls.
- drop unnecessary double quotes in Perl.
- clang-format.

Closes #21000

lib/url.c

@@ -386,7 +386,7 @@ void Curl_init_userdefined(struct Curl_easy *data)
 #endif
 
   set->new_file_perms = 0644;    /* Default permissions */
-  set->allowed_protocols = (curl_prot_t) CURLPROTO_64ALL;
+  set->allowed_protocols = (curl_prot_t)CURLPROTO_64ALL;
   set->redir_protocols = CURLPROTO_REDIR;
 
 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)