Basic application setup (#1)

This PR contains the work done to define the necessary setup from which the app will be built upon.

To provide further details on what has been done:
* created the app, the unit tests and the UI tests targets in the Xcode project;
* updated the bundle identifiers and OS deployment targets of all targets;
* added a `.gitignore` file tailored specifically for the project;
* added a `README` file that defines in details the goal of the project;
* added the [Swift Format](https://github.com/swiftlang/swift-format) rules that the source code should abide to;
* cleaned the boilerplate source code on all targets.

Reviewed-on: rock-n-code/todos-app#1
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

UITests/TodosUITestsLaunchTests.swift

@@ -0,0 +1,27 @@
+import XCTest
+
+final class TodosUITestsLaunchTests: XCTestCase {
+
+    override class var runsForEachTargetApplicationUIConfiguration: Bool {
+        true
+    }
+
+    override func setUpWithError() throws {
+        continueAfterFailure = false
+    }
+
+    @MainActor
+    func testLaunch() throws {
+        let app = XCUIApplication()
+        app.launch()
+
+        // Insert steps here to perform after app launch but before taking a screenshot,
+        // such as logging into a test account or navigating somewhere in the app
+
+        let attachment = XCTAttachment(screenshot: app.screenshot())
+        attachment.name = "Launch Screen"
+        attachment.lifetime = .keepAlways
+        add(attachment)
+    }
+
+}