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>

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/MatrixAuthenticationService.kt

@@ -43,7 +43,10 @@ interface MatrixAuthenticationService {
     /**
      * Get the Oidc url to display to the user.
      */
-    suspend fun getOidcUrl(prompt: OidcPrompt): Result<OidcDetails>
+    suspend fun getOidcUrl(
+        prompt: OidcPrompt,
+        loginHint: String?,
+    ): Result<OidcDetails>
 
     /**
      * Cancel Oidc login sequence.