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.

rojo-test/serve-tests/live_syncback/default.project.json5

@@ -0,0 +1,18 @@
+{
+  "name": "live_syncback",
+  "tree": {
+    "$className": "DataModel",
+    "ReplicatedStorage": {
+      "$className": "ReplicatedStorage",
+      "$path": "src/shared"
+    },
+    "ServerScriptService": {
+      "$className": "ServerScriptService",
+      "$path": "src/server"
+    },
+    "Workspace": {
+      "$className": "Workspace",
+      "$path": "src/workspace"
+    }
+  }
+}