[Message actions] New UI for replies (#545)

* Add 'reply to' UI to the message composer.

* Move the `BlurHashAsyncImage` to `:libraries:designsystem` as it is now used in several modules.

*  Create reusable `AttachmentThumbnail` and associated data classes and enums, it's now added to `:libraries:matrixui`.

* Re-use `AttachmentThumbnail` in a `ActionListView` and `TextComposer`.

* Add 'inReplyTo' models and UI.

* Add min size for images

* Create a separate layout for media items with no reply to info. Also, separate `Timeline__Row` components from `TimelineView`, as it was getting too large.

* Added `EqualWidthColumn` to use inside message bubbles. Also fixed some modifiers for media items replying to other messages.

* Disable `inReplyToClicked`.

* Remove unused resources and libraries.

* Remove any traces of `BlurHashAsyncImage` in `:features:messages`, since it was moved to the design system.

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

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventContent.kt

@@ -28,11 +28,25 @@ sealed interface EventContent
 
 data class MessageContent(
     val body: String,
-    val inReplyTo: EventId?,
+    val inReplyTo: InReplyTo?,
     val isEdited: Boolean,
     val type: MessageType?
 ) : EventContent
 
+
+sealed interface InReplyTo {
+    data class NotLoaded(val eventId: EventId) : InReplyTo
+    data class Ready(
+        val eventId: EventId,
+        val content: MessageContent,
+        val senderId: UserId,
+        val senderDisplayName: String?,
+        val senderAvatarUrl: String?,
+    ) : InReplyTo
+
+    object Error : InReplyTo
+}
+
 object RedactedContent : EventContent
 
 data class StickerContent(

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/timeline/item/event/EventTimelineItem.kt

@@ -32,4 +32,12 @@ data class EventTimelineItem(
     val senderProfile: ProfileTimelineDetails,
     val timestamp: Long,
     val content: EventContent
-)
+) {
+    fun inReplyTo(): InReplyTo? {
+        return (content as? MessageContent)?.inReplyTo
+    }
+    fun hasNotLoadedInReplyTo(): Boolean {
+        val details = inReplyTo()
+        return details is InReplyTo.NotLoaded || details is InReplyTo.Error
+    }
+}