docs: updates to use man(7) macros to fix formatting

docs/mm.1

@@ -2,62 +2,41 @@
 .\"
 .\" This work is licensed under CC BY-SA 4.0. To see a copy of this license,
 .\" visit <http://creativecommons.org/licenses/by-sa/4.0/>.
-
+.\"
 .TH mm 1
-
 .SH NAME
-
 mm \(en middleman
-
 .SH SYNOPSIS
-
+.\"
 mm
 .RB ( -aenu )
 .RB ( -i
 .RB [ input ])
 .RB ( -o
 .RB [ output ])
-
+.\"
 .SH DESCRIPTION
-
+.\"
 Catenate input files and write them to the start of each output file or stream.
-
+.\"
 .SH OPTIONS
-
-.B -a
-.RS
+.\"
+.IP -a
 Opens subsequent outputs for appending rather than updating.
-.RE
-
-.B -e
-.RS
+.IP -e
 Use the standard error as an output.
-.RE
-
-.B -i
-.RS
+.IP -i
 Opens a path as an input. Without any inputs specified mm will use the
 standard input. The standard input shall be used as an input if one or more of
 the input files is “-”.
-.RE
-
-.B -o
-.RS
+.IP -o
 Opens a path as an output. Without any outputs specified mm will use the
 standard output. The standard output shall be used as an output if one or more
 of the output files is “-”.
-
-.RE
-
-.B -u
-.RS
+.IP -u
 Ensures neither input or output will be buffered.
-.RE
-
-.B -n
-.RS
+.IP -n
 Causes SIGINT signals to be ignored.
-.RE
 
 .SH DIAGNOSTICS
 
@@ -84,5 +63,7 @@ Copyright (c) 2024 DTB. License AGPLv3+: GNU AGPL version 3 or later
 <https://gnu.org/licenses/agpl.html>.
 
 .SH SEE ALSO
-
-cat(1p), dd(1), dj(1), tee(1p)
+.BR cat (1p),
+.BR dd (1),
+.BR dj (1),
+.BR tee (1p)