open the inspector without the view transition

[pfefferle]

Proposed changes:

The inspector's corners jumped when it opened, and the whole stage folded during the transition. Two causes:

• Boot rounds the inspector with --wpds-border-radius-xl (12px) and draws its view-transition snapshots with that radius; we forced the panel to a hard 8px through --wpds-border-radius-large, a token that does not exist, and put a second 8px surface inside it. The override and the inner surface are gone, and our stage card uses the same xl token, so everything matches.
• Boot animates the stage as one flat surface, a pinned-corner crossfade while it resizes. Our stage is a dark shell around a card, so that reads as folding. The six navigations that open or close the inspector (post click, close button, the Feed menu item, actor switch, tag and type filter) now pass viewTransition: false to the router; nothing animates, and no boot internals are styled for it.

Other information:

• Have you written new tests for your changes, if applicable?

Testing instructions:

• Open the Social Web screen, click a post: the inspector appears with the same rounded corners and the same top/bottom edges as the list card, no animation. Close it with the X or via "Feed" in the sidebar: same.
• Switch the actor or pick a tag in the inspector: it closes without animation.