[PM-41870] Allow save prompt and fallback to writable collection when organization data ownership is enabled

[woliver99]

🎟️ Tracking

Closes #7256 PM-41838

📔 Objective

1. Removes an early return in AutofillProcessorImpl.kt that was automatically canceling Autofill save requests whenever ORGANIZATION_DATA_OWNERSHIP policy was enabled.
2. Updates getDefaultCollectionViewOrNull() in CipherViewExtensions.kt so that when DEFAULT_USER_COLLECTION is null, the app automatically selects the first writable collection as a fallback for much better UX.

📸 Screenshots

1. Autofill Save Prompt

Before	After

2. Collection Default Selection

Before	After

[CLAassistant]

All committers have signed the CLA.

[bitwarden-bot]

Thank you for your contribution! We've added this to our internal tracking system for review.
ID: PM-41870
Link: https://bitwarden.atlassian.net/browse/PM-41870

Details on our contribution process can be found here: https://contributing.bitwarden.com/contributing/pull-requests/community-pr-process.

[woliver99]

Just realised that auto-selecting the first collection might lead to saving into the wrong collection if a user has access to multiple collections.

What if instead we only auto-select if there’s exactly one collection available? That way if they have multiple collections, they’re still forced to pick one. This would also match how the web extension and desktop app handle it.

Let me know if you prefer that and I can update the code!