Add support for login link (#4752)

* Add support for login link

https://mobile.element.io/element?account_provider=example.org&login_hint=mxid:@alice:example.org

* Update screenshots

* Reduce code duplication

* Add test on OnBoardingPresenter

* Fix tool

* Ignore login parameter if user is not allowed to connect to the provided server.

* Improve tests.

* Cleanup

* Revert change on Project.xml.

* Add documentation

* Improve LoginHelper

* Rename LoginFlow to LoginMode

Move LoginFlow to package io.element.android.features.login.impl.login
Rename some implementation of LoginMode
Rename LoginFlowView to LoginModeView

* Change launchMode of MainActivity from `singleTop` to `singleTask`

Using launchMode singleTask to avoid multiple instances of the Activity when the app is already open. This is important for incoming share and for opening the application from a mobile.element.io link.

Closes #4074

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Co-authored-by: ElementBot <android@element.io>

appnav/build.gradle.kts

@@ -53,6 +53,7 @@ dependencies {
     testImplementation(libs.molecule.runtime)
     testImplementation(libs.test.truth)
     testImplementation(libs.test.turbine)
+    testImplementation(projects.features.login.test)
     testImplementation(projects.libraries.matrix.test)
     testImplementation(projects.libraries.oidc.impl)
     testImplementation(projects.libraries.preferences.test)