Sliding Sync + New Timeline API (#189)

* Begin adopting new Timeline API.

* Add edited indicator and reactions.

* vector-im/element-x-ios/issues/65 - Sliding sync support
* Fix missing room display name, wrong placeholder avatar text color and various other warnings that would fail the build on the CI

* Various tweaks:
* using release version of the demo branch of the sdk
* enabled home screen last room messages
* switched debug mode rust logging to warn
* enabled redactions
* enabled new logout flows and soft logout
* enabled replies

* Fix room member display name and avatar crashes / race condition, fix unit tests
* Make the ClientProxy and the UserSession MainActors
* Remove unused MatrixRustSDK imports, we should strive to keep these only in top level services and proxies
* Don't start either of the syncs while in soft logout

* #181: Style the session verification banner to match Figma.
* #181: Update verification modal.
* #181: Update snapshot tests.

* Make session verification state machine less pedantic
* Remove unnecessary weak selfs
* Various tweaks following code review:
* add start and stop sync client proxy methods
* move ss proxy url the build settings
* made media provider load results discardable
* added publishers for the roomSummaryProvider's total number of rooms and state

* Fix when sender details are shown
* Disable sync v2, causes duplicates in the timeline (as expected)
* Move ClientProxy media loading off the main queue and into a detached task
* Another attempt at moving image loading off the main queue
* Moved home screen diffing and latest room fetching to the background
* Prevent the timeline composer from becoming the first responder when not needed

* Bump to a newer version of the RustSDK

* Fixes vector-im/element-x-ios/issues/107 - New home screen design
* Implement thumbnail loading instead of full image avatars.
* Revert "Disable sync v2, causes duplicates in the timeline (as expected)"
* Add support for local echoes, dispatching detached tasks to a concurrenc GCD queue
* Move the session verification banner to a List Section to avoid UI glitches
* Optimise room mapping after sliding sync updates and thumbnail fetching
* Replace home screen List with a LazyVStack in an attempt to fix performance. Moved move summary provider room updating to a background thread

* Fixes vector-im/element-x-ios/issues/177 - New Bubbles Design
* Define in group state for timeline items
* Add replies into the bubble
* Add timeline width environment value
* Add `RoundedCorner` shape with specific corners rounding
* Add in group state for previews
* Implement bubble grouping logic
* Timeline avatar layout changes
* Fix placeholder avatars for dark mode
* New bubbles design
* Update mock timeline items
* Update timeline separator design
* Update room screen reference screenshots
* Add changelog
* Formatting fixes
* Add some space before single or beginning outgoing items

* Redesign the message composer

* Handle the msgtype enum.

* Update room name label line limit and incoming bubble background. Disabled syncv2, ss withCommonExtensions and session verification controller checking

* Increase default back pagination limit.
* Stop parsing links and tidy up composer button.
* Also fix the frame of an image whilst loading.
* Bump SDK package version.

* Remove app states about settings
* Add strings
* Use colors on placeholder avatars
* Tiny changes for placeholder avatars
* Update settings screen design
* Provide a user display name from the mock client
* Settings screen presentation logic
* Add changelog
* Update reference screenshots

Co-authored-by: Doug <douglase@element.io>
Co-authored-by: ismailgulek <ismailgulek@users.noreply.github.com>
Co-authored-by: ismailgulek <ismailg@matrix.org>

ElementX/Sources/Services/Room/RoomProxyProtocol.swift

@@ -15,22 +15,20 @@
 //
 
 import Combine
-import UIKit
+import MatrixRustSDK
 
 enum RoomProxyError: Error {
     case failedRetrievingDisplayName
     case failedRetrievingAvatar
-    case backwardStreamNotAvailable
+    case noMoreMessagesToBackPaginate
+    case failedPaginatingBackwards
     case failedRetrievingMemberAvatarURL
     case failedRetrievingMemberDisplayName
     case failedSendingMessage
     case failedRedactingEvent
 }
 
-enum RoomProxyCallback {
-    case updatedMessages
-}
-
+@MainActor
 protocol RoomProxyProtocol {
     var id: String { get }
     var isDirect: Bool { get }
@@ -43,12 +41,17 @@ protocol RoomProxyProtocol {
     var displayName: String? { get }
     
     var topic: String? { get }
-    var messages: [RoomMessageProtocol] { get }
     
     var avatarURL: String? { get }
     
+    var timelineProvider: RoomTimelineProviderProtocol { get }
+    
+    func avatarURLStringForUserId(_ userId: String) -> String?
+    
     func loadAvatarURLForUserId(_ userId: String) async -> Result<String?, RoomProxyError>
     
+    func displayNameForUserId(_ userId: String) -> String?
+    
     func loadDisplayNameForUserId(_ userId: String) async -> Result<String?, RoomProxyError>
     
     func loadDisplayName() async -> Result<String, RoomProxyError>
@@ -58,8 +61,6 @@ protocol RoomProxyProtocol {
     func sendMessage(_ message: String, inReplyToEventId: String?) async -> Result<Void, RoomProxyError>
     
     func redact(_ eventID: String) async -> Result<Void, RoomProxyError>
-    
-    var callbacks: PassthroughSubject<RoomProxyCallback, Never> { get }
 }
 
 extension RoomProxyProtocol {