Implement MORE.COM command

[FeralChild64]

Added MORE.COM command native implementation - available on drive Z:

Supports MS-DOS 7.0 (Windows 95) and FreeDOS extensions. I have tried to make the output as user friendly as possible.
Note that some wild ANSI escape sequences (like cursor movements) might disrupt the output - it would be really hard to make MORE.COM fully resistant.

Some files I used for testing: testfiles.tar.gz

[FeralChild64]

As discussed on Discord - some extensions from #1556 should be included in the implementation. Converting to draft for now.

[kcgen]

No comments; code is very readable and testing are running nicely.

@FeralChild64 , if you can rebase against main, I moved the resource's file reader internal routine to a generic file utility, which you can use (if you're adding the file-reading):

#include "fs_utils.h"

// MORE's FILENAME as non-null char*, std::string, or std_fs::path
// (no filesystem checks needed, get_lines will do it)
const auto text_file = ...

const auto lines = get_lines(text_file);

if (!lines)
    // the file could not be read, bail out

// iterate over zero or more std::string lines
for (const auto & line : *lines) {
    ...
}

[Kappa971]

A mistake:

COMMAND is the command to diplay output one screen at a time.

[kcgen]

Looks great @FeralChild64. A couple very minor comments.
Approved; feel free to merge when ready.

[FeralChild64]

@kcgen It's still a draft. I haven't tested everything, and the FreeDOS multi-file viewing is not yet implemented (I'll have to be careful here to not break the visual side).

I'll mark it as 'Ready for review' and re-request the review when I'm done - hard to tell precisely what changes I'll do.

[kcgen]

I'll mark it as 'Ready for review' and re-request the review when I'm done - hard to tell precisely what changes I'll do.

sounds good. Will review again when ready!

(PS- Merges are blocked for drafts, so there's no risk of accidental merge in the meantime)

[kcgen]

All comments addressed 🚀