Support iPadOS (iPad) & iOS (iPhone) apps in non-`get`/`install`/`update` commands

[rgoldberg]

Overview

Support iPadOS (iPad) & iOS (iPhone) apps in non-get/install/update commands:

When app IDs are (or --all is) supplied to a non-get/install/update command, the command should process each app ID regardless of the app's platform.

Commands

All commands that output apps should include a platform field in tabular & JSON output that indicates the platform of the app: macOS, iOS, iPadOS, Mac Catalyst, or anything else.

The following commands should process all apps regardless of platform:

• home
• list
• lookup/info
• open
• outdated (--accurate is macOS-only)
• search
• seller/vendor
• uninstall

--platforms

Maybe add support for a --platforms option for when a command is run without app IDs:

platforms_option ::= "--platforms" <platform> [ "," <platform> ]…`
platform ::= "macos" | "ios" | "ipados" | "all"

<platform> would probably be case insensitive.

--platforms would default to all (or maybe macos).

[rgoldberg]

IIRC, I have mainly finished this locally, except for:

1. Updating error outputs if an app cannot be processed because of its platform.
2. Testing.

This is blocked by #1226, which will allow selective output of fields, including platform.

#1226 is taking some time, as the spec is complex. Its initial release won't include all specced functionality, but it was useful to spec out many future improvements given the terseness & power of the syntax.

#838 would be useful for this to save configs for both fields & platform, but that requires macOS 15+ & a decent amount of work, so probably won't be a blocker.