Allow modifying smart app id/arguments from nextcloud apps

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Is your feature request related to a problem? Please describe.
Currently when opening a Nextcloud instance on an apple iOS device (iPhone, iPad) a smart app banner is displayed which links to the Nextcloud iOS Files app (allowing to open or install it).
This is added to every site in the templates, for users for example here:

https://github.com/nextcloud/server/blob/5b7f81b1b512d5b6038171a00d058bf3967c6d0d/core/templates/layout.user.php#L28-L30

The ID is retrieved here from the config:
https://github.com/nextcloud/server/blob/5b7f81b1b512d5b6038171a00d058bf3967c6d0d/lib/private/legacy/OC_Defaults.php#L68

so it can be changed on a per instance configuration in the config file:

https://github.com/nextcloud/server/blob/5b7f81b1b512d5b6038171a00d058bf3967c6d0d/config/config.sample.php#L1066-L1067

It is currently not possible for a nextcloud app to

1. change that id (for example it makes sense to show Nextcloud iOS Talk when you visit a Talk link)
2. add arguments to that link (for example if the Nextcloud iOS Files app is already installed, we could jump directly to that folder inside the app)

Describe the solution you'd like
We should find a way to present iOS apps depending on the currently open app in Nextcloud (Files => iOS Files, Talk => iOS Talk, Notes => iOS Notes, ...). Furthermore the Nextcloud apps should be able to adjust the arguments of the meta header tag (<meta name="apple-itunes-app" content="app-id=myAppStoreID, app-argument=myURL">).

Describe alternatives you've considered
Keep everything as is.

Additional context
Apple docs https://developer.apple.com/documentation/webkit/promoting_apps_with_smart_app_banners

Start with core/templates/layout.user.php and trace how the value from lib/private/legacy/OC_Defaults.php and config/config.sample.php reaches the apple-itunes-app meta tag. Review the Apple smart app banner documentation and determine how Nextcloud apps could provide an app ID and app argument based on the current app. Done means app-specific IDs and arguments can be supplied without changing the instance-wide configuration.