Handle sync code pasting

[MiSikora]

Task/Issue URL: https://app.asana.com/1/137249556945/project/1216103556496795/task/1216955858261368?focus=true
Tech Design URL (if applicable): https://app.asana.com/1/137249556945/project/1216103556496795/task/1216509582049467?focus=true
API Proposals URL(s) (if applicable): N/A

Description

Adds the manual code entry UI to the "Enter Code" tab of the simplified Sync With Another Device screen.

• The "Enter Code" tab now shows instructions for finding the code in the DuckDuckGo app on the other device, an example of what a sync code looks like, and a "Paste Sync Code" button.
• Tapping "Paste Sync Code" reads the clipboard and validates the content as a sync pairing URL.
• When the code is pasted, the sync process starts. For now this opens a temporary placeholder screen, SyncAnotherDeviceActivity.
• When the placeholder screen closes, the Sync With Another Device screen closes as well and the user returns to Sync Settings.

Steps to test this PR

Paste a valid sync code

• Open Sync Dev Settings.
• Tap "Launch Sync Settings V2".
• Tap "Sync With Another Device".
• Complete the device authentication prompt.
• Tap the "Show QR Code" icon in the toolbar.
• Tap "Copy Text Code".
• Go back to the Sync With Another Device screen.
• Open the "Enter Code" tab.
• Verify the tab shows the instructions, the example code, and the "Paste Sync Code" button.
• Tap "Paste Sync Code".
• Verify a placeholder screen opens showing the pasted sync URL on a magenta background.
• Go back.
• Verify the Sync With Another Device screen closed as well, returning you to Sync Settings.

UI changes

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Note

Medium Risk
Touches sync pairing entry and clipboard handling on a security-sensitive path; real pairing is still stubbed, but pasted content is passed forward without validation in this change.

Overview
The Enter Code tab on Sync With Another Device is no longer a stub: it shows pairing instructions, an example sync code, and a Paste Sync Code button wired through ReadSyncCodeViewModel and shared activity-scoped commands.

Paste Sync Code reads the clipboard and emits StartSyncProcess; ReadSyncCodeActivity launches the new ExchangeSyncCodeActivity via ExchangeSyncCodeContract and finishes the read-sync screen when that flow returns. ExchangeSyncCodeActivity is a temporary placeholder (magenta background, pasted URL text) registered in the manifest.

Strings for manual entry and an invalid-paste message are added; the diff does not wire validation or show the invalid message on paste.

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• To see the specific tasks where the Asana app for GitHub is being used, see below:
  • https://app.asana.com/0/0/1216981415686935

[MiSikora]

• Simplified sync translations #9414
• Parameterize sync pixels tests #9413
• Apply correct edge to edge handling in simplified sync #9412
• Add simplified sync pixels #9401
• Clean up sync code before integrating pixels #9386
• Avoid signing out of a device when renaming it #9374
• Handle simplified sync deep linking #9373
• Handle restore on reinstall sync scenario #9368
• Simplified sync UI updates #9363
• Handle v1 exchange sync codes #9362
• Handle sync recovery basic scenario #9356
• Add syncing with another device logic and navigation #9343
• Add generic handling of v1 sync errors #9337
• Add sync with another device UI #9334
• Detect scanned QR sync codes #9333
• Handle sync code pasting #9332 👈 (View in Graphite)
• Refactor simplified sync class names #9329
• Handle sync logic on the displayed QR code page #9328
• Display sync QR code in simplified sync #9321
• Make remove device dialog destructive #9317
• Mitigate sync settings UI race condtions #9316
• develop

This stack of pull requests is managed by Graphite. Learn more about stacking.

[MiSikora]

Merge activity

• Jul 30, 10:42 AM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jul 30, 11:15 AM UTC: Graphite couldn't merge this pull request because a downstack PR Handle sync logic on the displayed QR code page #9328 failed to merge.
• Jul 30, 12:31 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jul 30, 12:42 PM UTC: Graphite rebased this pull request as part of a merge.
• Jul 30, 12:58 PM UTC: @MiSikora merged this pull request with Graphite.

[cursor]

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

There are 2 total unresolved issues (including 1 from previous review).

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^{Reviewed by Cursor Bugbot for commit fc63823. Configure here.}

[cursor]

Manifest label is wrong copy-paste from QR activity

Low Severity

ExchangeSyncCodeActivity uses android:label="@string/sync_scanner_v2_qr_code_screen_title" which resolves to "QR Code". This was clearly copy-pasted from the DisplayQrCodeActivity entry directly above it. The label appears in the system task manager/recent apps and doesn't reflect what this activity actually does (sync code exchange).

 

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[MiSikora]

I'll fix that in the upper branches of the stack