Unicode awareness Part 2 -- copytext() (#48512)

* Unicode support Part 2 -- copytext()

This is the transition of all copytext() calls to be unicode aware and also some nearby calls in the same functions. Most things are just replacing copytext() with copytext_char() as a terrible character limiter but a few others were slightly more involved.

I replaced a ton of
````
var/something = sanitize(input())
something = copytext(something, 1, MAX_MESSAGE_LEN)
````

with a single stripped_input() call. stripped_input() already calls html_encode(), trim(), and some other sanitization so there shouldn't be any major issues there.

This is still VERY rough btw; DNA is a mess, the status displays are complete ass, there's a copytext() in code\datums\shuttles.dm that I'm not sure what to do with, and I didn't touch anything in the tools folder. I haven't tested this much at all yet, I only got it to compile earlier this morning. There's also likely to be weird bugs until I get around to fixing length(), findtext(), and the rest of the string procs.

* Makes the code functional

* Assume color hex strings are always # followed by ascii.
Properly encodes and decodes the stuff in mob_helpers.dm which fixes some issues there.

* Removes ninjaspeak since it's unused

code/modules/mining/machine_silo.dm

@@ -235,5 +235,5 @@ GLOBAL_LIST_EMPTY(silo_access_logs)
 		var/val = round(materials[key]) / MINERAL_MATERIAL_AMOUNT
 		msg += sep
 		sep = ", "
-		msg += "[amount < 0 ? "-" : "+"][val] [copytext(key, 2)]"
+		msg += "[amount < 0 ? "-" : "+"][val] [copytext(key, length(key[1]) + 1)]"
 	formatted = msg.Join()