Replace 'leave room' text with 'leave conversation' for DMs (#2231)

* Replace 'leave room' text with 'leave conversation' for DMs

* Add `isDm` property to both `RoomSummary` and `RoomListRoomSummary`

* Remove redundant `leave_conversation_alert_subtitle_*` texts

* Fix maestro flow

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Co-authored-by: ElementBot <benoitm+elementbot@element.io>

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/room/MatrixRoom.kt

@@ -52,6 +52,9 @@ interface MatrixRoom : Closeable {
     val activeMemberCount: Long
     val joinedMemberCount: Long
 
+    /** Whether the room is a direct message. */
+    val isDm: Boolean get() = isDirect && isOneToOne
+
     val roomInfoFlow: Flow<MatrixRoomInfo>
 
     /**

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/roomlist/RoomSummary.kt

@@ -45,4 +45,5 @@ data class RoomSummaryDetails(
     val inviter: RoomMember? = null,
     val notificationMode: RoomNotificationMode? = null,
     val hasOngoingCall: Boolean = false,
+    val isDm: Boolean = false,
 )