Rebuild UI test foundation with page objects, wait helpers, and screen objects

Replace brittle localized-string selectors and broken wait helpers with a
robust, identifier-first UI test infrastructure. All 41 UI tests pass on
iOS 26.2 simulator (iPhone 17).

Foundation:
- BaseUITestCase with deterministic launch helpers (launchClean, launchOffline)
- WaitHelpers (waitUntilHittable, waitUntilGone, tapWhenReady) replacing sleep()
- UITestID enum mirroring AccessibilityIdentifiers from the app target
- Screen objects: TabBarScreen, CameraScreen, CollectionScreen, TodayScreen,
  SettingsScreen, PlantDetailScreen

Key fixes:
- Tab navigation uses waitForExistence+tap instead of isHittable (unreliable
  in iOS 26 simulator)
- Tests handle real app state (empty collection, no camera permission)
- Increased timeouts for parallel clone execution
- Added NetworkMonitorProtocol and protocol-typed DI for testability
- Fixed actor-isolation issues in unit test mocks

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

PlantGuideUITests/Screens/PlantDetailScreen.swift

@@ -0,0 +1,61 @@
+//
+//  PlantDetailScreen.swift
+//  PlantGuideUITests
+//
+//  Screen object for the Plant Detail view.
+//
+
+import XCTest
+
+struct PlantDetailScreen {
+    let app: XCUIApplication
+
+    // MARK: - Elements
+
+    var detailView: XCUIElement {
+        app.otherElements[UITestID.PlantDetail.detailView]
+    }
+
+    var plantName: XCUIElement {
+        app.staticTexts[UITestID.PlantDetail.plantName]
+    }
+
+    var favoriteButton: XCUIElement {
+        app.buttons[UITestID.PlantDetail.favoriteButton]
+    }
+
+    var editButton: XCUIElement {
+        app.buttons[UITestID.PlantDetail.editButton]
+    }
+
+    var deleteButton: XCUIElement {
+        app.buttons[UITestID.PlantDetail.deleteButton]
+    }
+
+    var careSection: XCUIElement {
+        app.otherElements[UITestID.PlantDetail.careSection]
+    }
+
+    var tasksSection: XCUIElement {
+        app.otherElements[UITestID.PlantDetail.tasksSection]
+    }
+
+    /// The back button in navigation bar (leads back to Collection).
+    var backButton: XCUIElement {
+        app.navigationBars.buttons.firstMatch
+    }
+
+    // MARK: - State Checks
+
+    @discardableResult
+    func waitForLoad(timeout: TimeInterval = 5) -> Bool {
+        // Wait for any navigation bar to appear (title is dynamic plant name)
+        app.navigationBars.firstMatch.waitForExistence(timeout: timeout)
+    }
+
+    // MARK: - Actions
+
+    func tapBack() {
+        backButton.tapWhenReady()
+    }
+}