qol[Demo]: Prevent local account creation when no Minecraft account is found and make the associated error better

[alexytomi]

No description provided.

[ThatStella7922]

Looks sane at first glance, will test on physical device before approval

[ThatStella7922]

Test scenario 1: Open amethyst, click add account, local account.

Result: The error shows up just fine.

Test scenario 2: Open amethyst, log into a Microsoft account that does not own the game (demo user).
Result: Demo game works normally. Can create a local user after signing into demo MS account.

Ending feedback:

• Is being able to create a local user after signing into a demo account intended functionality?
• Please make the strings localizable

[alexytomi]

Thanks!

Is being able to create a local user after signing into a demo account intended functionality?

No it is not, logic at 2 am is not a good idea.

Please make the strings localizable

Done! Although the names may be a bit lengthy, I'm bad at naming things

[ThatStella7922]

The artifact tested: https://github.com/alexytomi/PojavLauncher/actions/runs/15783282077 app-debug-noruntime

App data was cleared between tests for a clean slate

Test scenario 1: Open amethyst, click add account, local account.
Result: Local account can be created without first adding a Microsoft account that owns Java Edition

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Test scenario 2: Open amethyst, log into a Microsoft account that does not own the game (demo user), click add account, local account.
Results: "No Minecraft Account Found, This feature requires a Microsoft account that owns Minecraft Java Edition" error.
Demo game also works normally. Pre-1.3.1 versions are also blocked with correct error.

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Ending feedback:
Good localization, but please fix the local account creation

[alexytomi]

Hope that fixes it 😭

[ThatStella7922]

Artifact tested: https://github.com/alexytomi/PojavLauncher/actions/runs/15792267715

App data cleared between runs

Test scenario 1: Open amethyst, click add account, local account.
Result: Error message is properly shown, nice

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Test scenario 2: Open amethyst, log into a Microsoft account that does not own the game (demo user), click add account, local account.
Result:

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Ending feedback:
Seems good to me. errors show up fine and the user can't add local accounts until a premium account is added, nor can they play anything pre-1.3.1 until that happens