Implement live syncback feature and enhance API for service data transfer

- Added a new `performSyncback` function in the `App` module to handle the synchronization of service data from the game to the server.
- Introduced a `SyncbackConfirm` UI component to confirm syncback actions from the user.
- Updated the API to include a new `/api/syncback` endpoint for handling syncback requests, validating protocol and server versions.
- Enhanced the `SyncbackSignal` mechanism to facilitate communication between the server and the syncback process.
- Added tests to ensure the functionality of the live syncback feature and its integration with the CLI.

These changes improve the overall synchronization capabilities of the application, allowing for real-time updates and better project management.

plugin/src/App/init.lua

@@ -1,8 +1,16 @@
 local ChangeHistoryService = game:GetService("ChangeHistoryService")
 local Players = game:GetService("Players")
+local SerializationService = game:GetService("SerializationService")
 local ServerStorage = game:GetService("ServerStorage")
 local RunService = game:GetService("RunService")
 
+local SYNCBACK_SERVICES = {
+	"Lighting", "MaterialService", "ReplicatedFirst", "ReplicatedStorage",
+	"ServerScriptService", "ServerStorage", "SoundService", "StarterGui",
+	"StarterPack", "StarterPlayer", "Teams", "TextChatService",
+	"VoiceChatService", "Workspace",
+}
+
 local Rojo = script:FindFirstAncestor("Rojo")
 local Plugin = Rojo.Plugin
 local Packages = Rojo.Packages
@@ -27,8 +35,11 @@ local ignorePlaceIds = require(Plugin.ignorePlaceIds)
 local timeUtil = require(Plugin.timeUtil)
 local Theme = require(script.Theme)
 
+local Http = require(Packages.Http)
+
 local Page = require(script.Page)
 local Notifications = require(script.Components.Notifications)
+local TextButton = require(script.Components.TextButton)
 local Tooltip = require(script.Components.Tooltip)
 local StudioPluginAction = require(script.Components.Studio.StudioPluginAction)
 local StudioToolbar = require(script.Components.Studio.StudioToolbar)
@@ -604,6 +615,68 @@ function App:useRunningConnectionInfo()
 	self.setPort(port)
 end
 
+function App:performSyncback()
+	self:setState({ showingSyncbackConfirm = false })
+
+	local host = self.host:getValue()
+	local port = self.port:getValue()
+
+	if host == "" then
+		host = Config.defaultHost
+	end
+	if port == "" then
+		port = Config.defaultPort
+	end
+
+	Promise.new(function(resolve, reject)
+		local services = {}
+		for _, className in SYNCBACK_SERVICES do
+			local ok, service = pcall(game.FindService, game, className)
+			if ok and service and #service:GetChildren() > 0 then
+				local buf = SerializationService:SerializeInstancesAsync(service:GetChildren())
+				table.insert(services, {
+					className = className,
+					data = buf,
+				})
+			end
+		end
+
+		local url = ("http://%s:%s/api/syncback"):format(host, port)
+		local body = Http.msgpackEncode({
+			protocolVersion = Config.protocolVersion,
+			serverVersion = Config.expectedServerVersionString,
+			placeId = game.PlaceId,
+			services = services,
+		})
+
+		Http.post(url, body)
+			:andThen(function(response)
+				if response.StatusCode >= 200 and response.StatusCode < 300 then
+					resolve()
+				else
+					reject(
+						`Syncback request failed ({response.StatusCode}): {response.Body or "unknown error"}`
+					)
+				end
+			end)
+			:catch(reject)
+	end)
+		:andThen(function()
+			Log.info("Syncback data sent to server.")
+			self:addNotification({
+				text = "Syncback data sent. Server is processing.",
+				timeout = 10,
+			})
+		end)
+		:catch(function(err)
+			Log.warn("Syncback failed: " .. tostring(err))
+			self:addNotification({
+				text = "Syncback failed: " .. tostring(err),
+				timeout = 10,
+			})
+		end)
+end
+
 function App:startSession()
 	-- If a session is already in progress, tear it down first.
 	-- In one-shot mode the sync lock is skipped, so this is the only guard
@@ -1027,23 +1100,29 @@ function App:render()
 				}, {
 					Tooltips = e(Tooltip.Container, nil),
 
-					NotConnectedPage = createPageElement(AppStatus.NotConnected, {
-						host = self.host,
-						onHostChange = self.setHost,
-						port = self.port,
-						onPortChange = self.setPort,
+				NotConnectedPage = createPageElement(AppStatus.NotConnected, {
+					host = self.host,
+					onHostChange = self.setHost,
+					port = self.port,
+					onPortChange = self.setPort,
 
-						onConnect = function()
-							self:startSession()
-						end,
+					onConnect = function()
+						self:startSession()
+					end,
 
-						onNavigateSettings = function()
-							self.backPage = AppStatus.NotConnected
-							self:setState({
-								appStatus = AppStatus.Settings,
-							})
-						end,
-					}),
+					onSyncback = function()
+						self:setState({
+							showingSyncbackConfirm = true,
+						})
+					end,
+
+					onNavigateSettings = function()
+						self.backPage = AppStatus.NotConnected
+						self:setState({
+							appStatus = AppStatus.Settings,
+						})
+					end,
+				}),
 
 					ConfirmingPage = createPageElement(AppStatus.Confirming, {
 						confirmData = self.state.confirmData,
@@ -1117,22 +1196,100 @@ function App:render()
 					}),
 				}),
 
-				RojoNotifications = e("ScreenGui", {
-					ZIndexBehavior = Enum.ZIndexBehavior.Sibling,
-					ResetOnSpawn = false,
-					DisplayOrder = 100,
-				}, {
-					Notifications = e(Notifications, {
-						soundPlayer = self.props.soundPlayer,
-						notifications = self.state.notifications,
-						onClose = function(id)
-							self:closeNotification(id)
-						end,
-					}),
+			RojoNotifications = e("ScreenGui", {
+				ZIndexBehavior = Enum.ZIndexBehavior.Sibling,
+				ResetOnSpawn = false,
+				DisplayOrder = 100,
+			}, {
+				Notifications = e(Notifications, {
+					soundPlayer = self.props.soundPlayer,
+					notifications = self.state.notifications,
+					onClose = function(id)
+						self:closeNotification(id)
+					end,
 				}),
 			}),
+		}),
 
-			toggleAction = e(StudioPluginAction, {
+		SyncbackConfirm = e(StudioPluginGui, {
+			id = "Atlas_SyncbackConfirm",
+			title = "Full Syncback",
+			active = self.state.showingSyncbackConfirm == true,
+			isEphemeral = true,
+
+			initDockState = Enum.InitialDockState.Float,
+			overridePreviousState = true,
+			floatingSize = Vector2.new(400, 150),
+			minimumSize = Vector2.new(300, 120),
+
+			zIndexBehavior = Enum.ZIndexBehavior.Sibling,
+
+			onClose = function()
+				self:setState({ showingSyncbackConfirm = false })
+			end,
+		}, {
+			Content = Theme.with(function(theme)
+				return e("Frame", {
+					Size = UDim2.fromScale(1, 1),
+					BackgroundColor3 = theme.BackgroundColor,
+					BorderSizePixel = 0,
+				}, {
+					Padding = e("UIPadding", {
+						PaddingLeft = UDim.new(0, 16),
+						PaddingRight = UDim.new(0, 16),
+						PaddingTop = UDim.new(0, 16),
+						PaddingBottom = UDim.new(0, 16),
+					}),
+					Layout = e("UIListLayout", {
+						FillDirection = Enum.FillDirection.Vertical,
+						SortOrder = Enum.SortOrder.LayoutOrder,
+						Padding = UDim.new(0, 16),
+						VerticalAlignment = Enum.VerticalAlignment.Center,
+					}),
+					Message = e("TextLabel", {
+						Text = "This will overwrite your project files with the current Studio state. This cannot be undone.",
+						TextWrapped = true,
+						FontFace = theme.Font.Main,
+						TextSize = theme.TextSize.Body,
+						TextColor3 = theme.TextColor,
+						Size = UDim2.new(1, 0, 0, 0),
+						AutomaticSize = Enum.AutomaticSize.Y,
+						BackgroundTransparency = 1,
+						LayoutOrder = 1,
+					}),
+					Buttons = e("Frame", {
+						Size = UDim2.new(1, 0, 0, 34),
+						BackgroundTransparency = 1,
+						LayoutOrder = 2,
+					}, {
+						Layout = e("UIListLayout", {
+							HorizontalAlignment = Enum.HorizontalAlignment.Right,
+							FillDirection = Enum.FillDirection.Horizontal,
+							SortOrder = Enum.SortOrder.LayoutOrder,
+							Padding = UDim.new(0, 10),
+						}),
+						Cancel = e(TextButton, {
+							text = "Cancel",
+							style = "Bordered",
+							layoutOrder = 1,
+							onClick = function()
+								self:setState({ showingSyncbackConfirm = false })
+							end,
+						}),
+						Confirm = e(TextButton, {
+							text = "Syncback",
+							style = "Danger",
+							layoutOrder = 2,
+							onClick = function()
+								self:performSyncback()
+							end,
+						}),
+					}),
+				})
+			end),
+		}),
+
+		toggleAction = e(StudioPluginAction, {
 				name = "AtlasConnection",
 				title = "Atlas: Connect/Disconnect",
 				description = "Toggles the server for an Atlas sync session",