Sync auto recovery detection in onboarding

[CDRussell]

Task/Issue URL: https://app.asana.com/1/137249556945/project/488551667048375/task/1213232213875727

Description

Adds sync auto-restore detection into WelcomePageViewModel so recovery key availability is checked in parallel with the welcome animation. When a previous sync recovery key is found (and the syncAutoRestore feature flag is enabled), a new "Restore My Stuff" Dax dialog is shown as the first dialog in onboarding.

Note, syncAutoRestore is disabled in this PR, meaning there is no production user-facing changes.

• New SYNC_RESTORE dialog type with primary CTA ("Restore My Stuff") triggering restoreSyncAccount(), secondary CTA ("Skip") going to the existing skip-onboarding flow
• F-Droid uses DummyPersistentStorage, so canRestore() returns false regardless

Steps to test this PR

ℹ️ Test on a device/emulator which has:

• Google Play Services available,
• and you're signed into Google account
• and you've set a device PIN/Password/Pattern (tip, go to Passwords screen in our app for a quick way to set it up)

Flag OFF (default — production behavior):

• Fresh install or uninstall/reinstall
• Verify normal onboarding flow is unchanged (no sync restore dialog appears)
• Reinstall users see the existing reinstall dialog as before

Flag ON, no recovery key stored:

• Enable syncAutoRestore feature flag by applying the patch below
• Uninstall and reinstall
• Verify normal onboarding flow (no sync restore dialog)

Flag ON, with recovery key available:

• Enable syncAutoRestore feature flag by applying the patch below
• Install app
• Go to Settings → Sync Dev Settings
• Verify you see ✅ syncAutoRestore flag enabled
• Verify you see ✅ Available
• Verify you see ✅ E2E encryption available
• In the Data to store text field, add a few characters and tap Write
• Verify it updates Current stored value to reflect what you typed
• Uninstall and reinstall the app (note, do not clear app data; needs to be an uninstall/reinstall)
• Verify "Let's pick up where you left off" dialog appears first in onboarding
• Tap "Restore My Stuff" → continues to comparison chart (this is a no-op under the hood right now)
• Alternatively, tap "Skip" → shows skip onboarding option

Patch to enable syncAutoRestore feature flag

Index: sync/sync-impl/src/main/java/com/duckduckgo/sync/impl/SyncFeature.kt
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/sync/sync-impl/src/main/java/com/duckduckgo/sync/impl/SyncFeature.kt b/sync/sync-impl/src/main/java/com/duckduckgo/sync/impl/SyncFeature.kt
--- a/sync/sync-impl/src/main/java/com/duckduckgo/sync/impl/SyncFeature.kt	(revision Staged)
+++ b/sync/sync-impl/src/main/java/com/duckduckgo/sync/impl/SyncFeature.kt	(date 1773146917281)
@@ -78,6 +78,6 @@
     @Toggle.DefaultValue(DefaultFeatureValue.TRUE)
     fun syncAutoRecoveryCapabilityDetectionRead(): Toggle
 
-    @Toggle.DefaultValue(DefaultFeatureValue.FALSE)
+    @Toggle.DefaultValue(DefaultFeatureValue.TRUE)
     fun syncAutoRestore(): Toggle
 }

UI changes

New Dax dialog shown conditionally during onboarding (flag-gated, disabled by default):

• Title: "Let's pick up where you left off"
• Description: "Want to restore your bookmarks, passwords, and more from your previous DuckDuckGo sync?"
• Primary: "Restore My Stuff"
• Secondary: "Skip"

---

Note

Medium Risk
Changes the onboarding entry dialog selection and wires in SyncAutoRestore checks/restore calls; although guarded by canRestore() and timeouts, any regressions could affect first-run onboarding behavior.

Overview
Adds a new PreOnboardingDialogType.SYNC_RESTORE and a corresponding onboarding command/UI path so eligible users can see a new "Restore My Stuff" dialog before the existing intro/reinstall flow.

WelcomePageViewModel now runs SyncAutoRestore.canRestore() asynchronously (with timeout + error handling/logging) and prioritizes showing the sync-restore dialog when possible; the primary CTA triggers restoreSyncAccount() then proceeds to the comparison chart, while the secondary CTA routes into the existing skip-onboarding option. Includes new UI strings, unit tests for the new branching/CTA behavior, and placeholder handling in the brand-design-update onboarding variant.

^{Written by Cursor Bugbot for commit 47a3750. Configure here.}

[CDRussell]

• Update sync settings screen with new recovery section #8008
• Add new sync screen for showing recovery code #7966
• Prevent orphaned sync devices when auto-restoring #7969
• Headless sync recovery implementation #7941
• Sync auto recovery detection in onboarding #7925 👈 (View in Graphite)
• Add SyncAutoRestore API and SyncRecovery key #7910
• develop

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

Bugbot Autofix prepared a fix for the issue found in the latest run.

• ✅ Fixed: Sync restore skip doesn't set reinstallUser flag
  • Added reinstallUser = true in the SYNC_RESTORE secondary CTA handler to match the INITIAL_REINSTALL_USER handler, ensuring correct event data when a sync restore user skips onboarding and later reaches the INPUT_SCREEN step.

Or push these changes by commenting:

@cursor push 8331d324f7

Preview (8331d324f7)

diff --git a/app/src/main/java/com/duckduckgo/app/onboarding/ui/page/WelcomePageViewModel.kt b/app/src/main/java/com/duckduckgo/app/onboarding/ui/page/WelcomePageViewModel.kt
--- a/app/src/main/java/com/duckduckgo/app/onboarding/ui/page/WelcomePageViewModel.kt
+++ b/app/src/main/java/com/duckduckgo/app/onboarding/ui/page/WelcomePageViewModel.kt
@@ -266,6 +266,7 @@
             SYNC_RESTORE -> {
                 viewModelScope.launch {
                     logcat { "Sync-AutoRestore: user skipped restore" }
+                    reinstallUser = true
                     _commands.send(ShowSkipOnboardingOption)
                 }
             }