Restore automatic tile-attribution rendering coverage

[stef-k]

Problem

The ordinary suite on the #507 feature branch consistently reports this failing test:

TileAttributionLayoutRenderingTests.SnapshotBackedViewerAndPrintOutputRenderResolvedProviderAttribution

Wayfarer is intended to resolve tile attribution automatically from the tile provider configured by an administrator. This issue does not request manual attribution configuration or a change to #507.

Required investigation

• Reproduce the focused failure from current main/the eventual Add resumable scheduled geocoding backfill for large history imports #507 base.
• Determine whether the stored snapshot is stale or production viewer/print attribution rendering regressed.
• Preserve automatic provider-derived attribution.
• Correct the smallest authoritative owner or snapshot.
• Verify viewer and print output, fallback behavior, encoding, and provider switching.
• Run the focused attribution selection and the ordinary suite before closure.

Release relationship

Tracked separately from #507. Link the result in the #507 PR if the failure remains relevant at publication time.

[stef-k]

Confirmed as a local Playwright prerequisite failure, not a tile-attribution product regression. The reported failure occurred at the PLAYWRIGHT_BROWSERS_PATH environment guard before rendering assertions. With the repository's established Playwright 1.62.0-compatible Chromium revision 1234 cache, the attribution class passed 4/4, the broader attribution selection passed 64/64, and the ordinary Release suite passed 2,624/2,624. Viewer, Print/PDF, provider switching, default/custom/blank attribution, sanitization, and HTML encoding remain correct. No code change was required.