[Preview] Windows: viewport toggle missing + URL truncated in Preview pane toolbar

Platform: Windows 11
Claude Code version: 2.1.138

Two regressions in the Claude Preview pane chrome on Windows, both in the same toolbar area above the rendered page:

1. Mobile / tablet / desktop viewport switcher buttons are gone.
Previously visible in the toolbar; clicking would flip the rendered viewport between presets. Now no buttons at all — viewport can only be changed by the agent calling mcp__Claude_Preview__preview_resize. The human-in-the-loop control is missing.

2. Full URL is no longer shown — truncated, requires a click to expand.
Previously the toolbar displayed the full URL of the page being previewed. Now the URL is collapsed regardless of window width; the user has to click to see the full string. This breaks the "glance to verify the agent went to the right URL" flow.

Both look like the same UI refactor of the Preview toolbar dropping previously-visible affordances. They feel related and probably regressed in the same release.

Related:

• #57844 — macOS confirmation of the viewport-toggle half of this.
• #58820 — narrower issue covering the URL-truncation half on Windows.