tidy-up: miscellaneous

- `N byte` -> `N-byte` or `N bytes`.
- INTERNALS.md: language tweaks.
- schannel: language tweak in comment/error message.
- socks_gssapi, socks_sspi: simplify composing an error message.
  (at a cost of 8 extra constant string bytes.)
- m4/curl-compilers.m4: fix typo in link (in comment).
- contrithanks.sh: fix indent, drop stray `;` terminator.
- lib, src, tests: drop/fix a bunch of badwords.
- fix typos in comments.
- fix indent, stray spaces.

Some of these spotted by GitHub Code Quality and Copilot

Closes #22009

scripts/top-complexity

@@ -96,7 +96,7 @@ my $alllines = 0;
 # 142     417     809     1677    1305    src/tool_getparam.c(1677): getparameter
 for my $l (@output) {
     chomp $l;
-    if($l =~/^(\d+)\t\d+\t\d+\t\d+\t(\d+)\t([^\(]+).*: ([^ ]*)/) {
+    if($l =~ /^(\d+)\t\d+\t\d+\t\d+\t(\d+)\t([^\(]+).*: ([^ ]*)/) {
         my ($score, $len, $path, $func) = ($1, $2, $3, $4);
 
         my $allow = 0;