Import textual fixes from fd-nls [closes #174] (#175)

Part of patch
~~~
commit 01c4ad0a496797e74fccee2e5ae61244f8e4e641
Author: Sebastian Rasmussen <sebras@gmail.com>
Date:   Thu Apr 10 00:21:02 2025 +0200

    Fix typos in the original English files for many projects.
~~~

Author: andrewbird

strings/DEFAULT.err

@@ -36,7 +36,7 @@
 # 
 # The individual words are defined by ABORT, IGNORE, RETRY, FAIL. They
 # should indicate which user response keys is associated with them;
-# suggested is to use the first letter and enclose it in parenthesises.
+# suggested is to use the first letter and enclose it in parentheses.
 # The delimiter ", " can be defined with DELIMITER and is the same
 # for all slots.
 # The "? " sequence is defined by QUESTION.

strings/DEFAULT.lng

@@ -15,7 +15,7 @@
 # outputs.  This file is the input to the fixstrs program, and it
 # outputs strings.h and strings.dat.  The .DAT file is appended to
 # the command.exe file, and then renamed to command.com.  The .H
-# file contains all the info for the program to retreive the
+# file contains all the info for the program to retrieve the
 # messages.
 #
 # The format of this file is simple.  Blank lines and lines starting
@@ -35,7 +35,7 @@
 #
 # All lines after the label are the message until a line with a
 # single "." or "," in the first column.  The difference is the
-# period (".") signifies that there will be a final carrage return when
+# period (".") signifies that there will be a final carriage return when
 # the message is displayed, but a comma does not.
 #
 # The body may contain backslash escape sequences as known from C; there
@@ -55,7 +55,7 @@
 
 # Defining prompts
 # Some prompts may cause an user interaction. Those ones should be in sync
-# with the issued text. To define how to interprete a pressed key, they
+# with the issued text. To define how to interpret a pressed key, they
 # are mapped into metakeys like that: [ignore first hash sign]
 
 ## Return value: a -> Yes; else -> No
@@ -67,9 +67,9 @@
 
 # All strings, which label start with "PROMPT_", are parsed as prompts.
 # The first two lines of the body are special; the first one enumerates all
-# valid keys, the second one assigns arbitary metakeys. Metakeys may
+# valid keys, the second one assigns arbitrary metakeys. Metakeys may
 # range from 'a' through 'z'; spaces are ignored; everything else cause
-# an error. The comment preceeding the prompt definition associates the
+# an error. The comment preceding the prompt definition associates the
 # metakeys with their meaning.
 # The remaining lines of the body contain the text to be displayed.
 #
@@ -80,7 +80,7 @@
 # 'N', 'n', Enter and ^Break are mapped to metakey 'b' (aka No).
 # The spaces between the 'b's in the second line had been inserted to
 # align them with the corresponding keys of the first line, hence in order
-# to enhance readibility of the association between the pressed keys and their
+# to enhance readability of the association between the pressed keys and their
 # mapping into a metakey.
 #
 # The first line (pressed keys) has to enumerate the ASCII value as returned