[AppDetails] Allowing opening the App Details page via...

[AppDetails] Allowing opening the App Details page via app-manager://details?id=<pkg>&user=<user_id>

The uri is similar to market://details?id=<pkg

> in addition to supporting an
optional user ID as a query parameter. If user ID is provided but does not exist
in system, it does not fall back to the default user ID to avoid inconsistent
behavior.

Signed-off-by: Muntashir Al-Islam <muntashirakon@riseup.net>