Add additional Obtainium information and fix typo in docker documentation

[BurgundyDev]

Description

Add a guide for adding the Android app via Obtainium and correct the tags in the Docker portion of the README.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings

AI disclosure:

• Partially AI assisted (clarify which code was AI assisted and briefly explain what it does).
• Fully AI generated (explain what all the generated code does in moderate detail).

No AI was used in making of this documentation

[monospacedmagic]

Obtainium doesn't work with the way nightly releases are set up currently, it doesn't realize there's a newer version. A potential fix would be to change the corresponding workflow to create a new nightly release and use the actual version string as the version string for the release rather than "nightly", then find the previous nightly release and delete it.

[hazre]

Seems to work?

[monospacedmagic]

It worked for me once as well, but after that it failed to detect any updates for me.

[cyrneko]

ok hi hello I've been using a stock config with

• sort method: release date
• use latest asset upload as release date
• use release date as version string (pseudo-version)

and in this combo nightlies work well. You can import that here