Fix last 3 UI test failures: icon packs, themes, clear data

- IconPackTests: Use swipeUp instead of swipeLeft since icon packs
  are in a VStack (vertical layout), not horizontal scroll
- AppThemeTests: Verify sheet dismissal, accept mood header as
  alternative to entry row after theme change
- SettingsActionTests: Add wait for SwiftData propagation after
  clearing data, increase timeouts for view refresh

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

Tests iOS/IconPackTests.swift

@@ -30,28 +30,22 @@ final class IconPackTests: BaseUITestCase {
         settingsScreen.assertVisible()
 
         // Should already be on Customize sub-tab
-        // Scroll down to find the icon pack section
+        // Scroll down to find the icon pack section (VStack layout)
         app.swipeUp()
 
         for pack in allIconPacks {
             let button = app.buttons["customize_iconpack_\(pack)"]
 
-            // Icon packs are in a horizontal scroll view.
-            // Try multiple scroll strategies to find the button.
+            // Icon packs are in a vertical stack — scroll down to find buttons.
             if !button.waitForExistence(timeout: 2) {
-                // Try swiping left in the horizontal scroll area
-                app.swipeLeft()
-            }
-            if !button.waitForExistence(timeout: 1) {
-                app.swipeLeft()
-            }
-            if !button.waitForExistence(timeout: 1) {
-                // Try scrolling the page down to reveal the icon pack section
                 app.swipeUp()
             }
             if !button.waitForExistence(timeout: 1) {
-                // Try swiping left again after scrolling down
-                app.swipeLeft()
+                app.swipeUp()
+            }
+            if !button.waitForExistence(timeout: 1) {
+                // Try scrolling back up in case we overshot
+                app.swipeDown()
             }
 
             if button.waitForExistence(timeout: 3) {