feat(ci): weekly alpha releases

[david-allison]

Note

Assisted-by: GPT-6

Purpose

Automatically publish on -4:30 UTC every Monday.

Skipped if:

• A publish occurred fewer than 7 UTC calendar days ago.
• The app is not in alpha.
• There were no commits since the last release.

Fixes

• Fixes Increase release cadence of alpha builds #20166

Approach

• add a gradle task to generate metadata to a .json file
• In CI: run everyMonday at 4:30, check the generated files and

How Has This Been Tested?

⚠️ CI - please provide suggestions
A small test was added to be sure the test wouldn't be broken if we renamed AnkiDroid

Checklist

• You have a descriptive commit message with a short title (first line, max 50 chars).
• You have commented your code, particularly in hard-to-understand areas
• You have performed a self-review of your own code
• UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• UI Changes: You have tested your change using the Google Accessibility Scanner

[mikehardy]

LGTM — after adversarial review + local CI-parity (lint/unit/emulator on API36_GAPI_PS16K) on a rebase onto current main.