Fix MacOSAppVersion ordering

[psobot]

Via my friend Claude:

Prerequisite for any multi-version work, but a real bug on its own.

The defect

__lt__ and __le__ OR'd three independent comparisons together instead of comparing lexicographically, so a version could sort below another in both directions at once. Not hypothetical — this is the exact pair in play:

14.4 < 14.5 -> True
14.5 < 14.4 -> True     # because "1A107s" < "1A89s" as plain strings

LATEST_VERSION is max(VERSIONS), and VERSIONS is built by iterating os.listdir(). So the moment a second version is bundled, which version counts as "latest" depends on directory order. With one version bundled this was invisible, which is why it survived.

It also affects the user-facing "your Keynote is newer than this parser supports" warning, which compares __supported_keynote_version__ < installed_version.

Three defects, one fix

	Before	Now
Antisymmetry	a < b and b < a both true	single tuple comparison
Digit runs	"1A107s" < "1A89s", "7043.0.93" < "7043.0.9"	split on digit runs, compared numerically
Differing lengths	short_version_comparator scaled by 10 ** (len - i), so 14.4.1 scored 14410 vs 14.5 at 1450 — older sorting higher	plain tuple comparison

Also adds __eq__ and __hash__ — previously two identical versions compared unequal, since equality fell back to identity — and derives the rest with functools.total_ordering.

Removal

short_version_comparator is gone. It was internal (the only references were inside this module) and its value wasn't meaningful across versions with differing component counts. Flagging it in case you consider it public API.

Verification

The new tests fail 6 of 9 against the previous implementation and pass against this one. Full suite 39 passed; lint and format clean.