Onboarding Experiment BB: Fix skip onboarding crash (#6573)

Task/Issue URL:
https://app.asana.com/1/137249556945/project/414730916066338/task/1211043239331636

### Description

Fixed memory leaks in the BbWelcomePage by properly canceling animations
when the view is destroyed. Added references to ViewPropertyAnimator and
ValueAnimator instances and ensured they are canceled in
onDestroyView().

### Steps to test this PR

Apply patch
```
Index: app/src/main/java/com/duckduckgo/app/onboardingdesignexperiment/OnboardingDesignExperimentManager.kt
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/app/src/main/java/com/duckduckgo/app/onboardingdesignexperiment/OnboardingDesignExperimentManager.kt b/app/src/main/java/com/duckduckgo/app/onboardingdesignexperiment/OnboardingDesignExperimentManager.kt
--- a/app/src/main/java/com/duckduckgo/app/onboardingdesignexperiment/OnboardingDesignExperimentManager.kt	(revision 8406810)
+++ b/app/src/main/java/com/duckduckgo/app/onboardingdesignexperiment/OnboardingDesignExperimentManager.kt	(date 1755086579929)
@@ -32,6 +32,8 @@
 import com.duckduckgo.common.utils.device.DeviceInfo.FormFactor.TABLET
 import com.duckduckgo.di.scopes.AppScope
 import com.duckduckgo.feature.toggles.api.MetricsPixel
+import com.duckduckgo.feature.toggles.api.Toggle
+import com.duckduckgo.feature.toggles.api.Toggle.State.Cohort
 import com.duckduckgo.privacy.config.api.PrivacyConfigCallbackPlugin
 import com.squareup.anvil.annotations.ContributesBinding
 import com.squareup.anvil.annotations.ContributesMultibinding
@@ -126,6 +128,13 @@
      * Eligibility is determined by the device's Android version, form factor, and whether the user is a returning user.
      */
     override suspend fun enroll() {
+        onboardingDesignExperimentToggles.onboardingDesignExperimentAug25().setRawStoredState(
+            Toggle.State(
+                remoteEnableState = true,
+                enable = true,
+                cohorts = listOf(Cohort(name = BB.cohortName, weight = 1)),
+            )
+        )
         withContext(dispatcherProvider.io()) {
             if (isEligibleForEnrolment()) {
                 onboardingDesignExperimentToggles.onboardingDesignExperimentAug25().enroll()
```

_Animation Cleanup_
- [x] Clear data
- [x] Delete DuckDuckGo folder from device `Download` folder
- [x] Launch app on good connection
- [x] Press skip onboarding before all animations can complete
- [x] Verify no crashes and browser screen launches

### UI changes
N/A

Author: mikescamell

app/src/main/java/com/duckduckgo/app/onboarding/ui/page/BbWelcomePage.kt

@@ -28,6 +28,7 @@ import android.graphics.Color
 import android.os.Bundle
 import android.view.View
 import android.view.ViewGroup.MarginLayoutParams
+import android.view.ViewPropertyAnimator
 import android.view.WindowManager
 import android.view.animation.DecelerateInterpolator
 import android.view.animation.PathInterpolator
@@ -90,6 +91,8 @@ class BbWelcomePage : OnboardingPageFragment(R.layout.content_onboarding_welcome
     }
 
     private var welcomeAnimation: ViewPropertyAnimatorCompat? = null
+    private var welcomeTitleAnimator: ViewPropertyAnimator? = null
+    private var daxDialogAnimator: ValueAnimator? = null
     private var daxDialogAnimationStarted = false
     private var backgroundSceneManager: BbOnboardingBackgroundSceneManager? = null
 
@@ -173,6 +176,8 @@ class BbWelcomePage : OnboardingPageFragment(R.layout.content_onboarding_welcome
     override fun onDestroyView() {
         super.onDestroyView()
         welcomeAnimation?.cancel()
+        welcomeTitleAnimator?.cancel()
+        daxDialogAnimator?.cancel()
     }
 
     override fun onActivityResult(
@@ -496,7 +501,7 @@ class BbWelcomePage : OnboardingPageFragment(R.layout.content_onboarding_welcome
             applyTo(binding.longDescriptionContainer)
         }
 
-        ValueAnimator.ofFloat(0f, 1f)
+        daxDialogAnimator = ValueAnimator.ofFloat(0f, 1f)
             .apply {
                 duration = transitionDuration.inWholeMilliseconds
                 startDelay = transitionDelay.inWholeMilliseconds
@@ -528,10 +533,11 @@ class BbWelcomePage : OnboardingPageFragment(R.layout.content_onboarding_welcome
                         height = calculateCurrentValue(initialHeight, targetHeight, progress)
                     }
                 }
+            }.also {
+                it.start()
             }
-            .start()
 
-        binding.welcomeTitle.animate()
+        welcomeTitleAnimator = binding.welcomeTitle.animate()
             .translationX(-resources.displayMetrics.widthPixels.toFloat())
             .setDuration(transitionDuration.inWholeMilliseconds)
             .setStartDelay(transitionDelay.inWholeMilliseconds)