Use the Emoji/Map/Poll view models. (#4458)

* Toggle emojis in the EmojiPickerScreenViewModel.

* Send locations in the StaticLocationScreen.

* Send polls in the PollFormScreen.

UnitTests/Sources/EmojiPickerScreenViewModelTests.swift

@@ -0,0 +1,45 @@
+//
+// Copyright 2025 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+// Please see LICENSE files in the repository root for full details.
+//
+
+import XCTest
+
+@testable import ElementX
+
+@MainActor
+final class EmojiPickerScreenViewModelTests: XCTestCase {
+    var timelineProxy: TimelineProxyMock!
+    
+    var viewModel: EmojiPickerScreenViewModel!
+    var context: EmojiPickerScreenViewModel.Context { viewModel.context }
+    
+    func testToggleReaction() async throws {
+        setupViewModel()
+        let reaction = "👋"
+        
+        let expectation = XCTestExpectation(description: "Toggle reaction")
+        let deferred = deferFulfillment(viewModel.actions) { $0 == .dismiss }
+        timelineProxy.toggleReactionToClosure = { toggledReaction, _ in
+            XCTAssertEqual(toggledReaction, reaction)
+            expectation.fulfill()
+            return .success(())
+        }
+        context.send(viewAction: .emojiTapped(emoji: .init(id: "wave", value: reaction)))
+        await fulfillment(of: [expectation], timeout: 1)
+        try await deferred.fulfill()
+    }
+    
+    // MARK: - Helpers
+    
+    private func setupViewModel(selectedEmojis: Set<String> = []) {
+        timelineProxy = TimelineProxyMock(.init())
+        
+        viewModel = EmojiPickerScreenViewModel(itemID: .randomEvent,
+                                               selectedEmojis: selectedEmojis,
+                                               emojiProvider: EmojiProvider(appSettings: ServiceLocator.shared.settings),
+                                               timelineController: MockTimelineController(timelineProxy: timelineProxy))
+    }
+}