Manpages: Auto-generate many through ArgsParser

This set was hand-curated, guided by the questions:
- Does it have at least three options, i.e. is the help page
  non-trivial?
- Is the program unusual, i.e. does listing it in Help or on
  man.serenityos.org spread awareness?
- Is the program common, but we only implement a subset of 'common'
  flags?

Base/usr/share/man/man1/truncate.md

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+## Name
+
+truncate
+
+## Synopsis
+
+```sh
+$ truncate [--size size] [--reference file] <file>
+```
+
+## Options:
+
+* `--help`: Display help message and exit
+* `--version`: Print version
+* `-s size`, `--size size`: Resize the target file to (or by) this size. Prefix with + or - to expand or shrink the file, or a bare number to set the size exactly
+* `-r file`, `--reference file`: Resize the target file to match the size of this one
+
+## Arguments:
+
+* `file`: File path
+
+<!-- Auto-generated through ArgsParser -->