Follow-up to #8: Add floating inline clip previews

[alvst]

Dependency

This draft builds on #8 (Add configurable clip previews). Its current diff intentionally includes #8 because GitHub cannot use a branch in this fork as the base of an upstream PR.

After #8 merges, this branch will be rebased onto upstream main; this PR will then show only the floating-preview follow-up.

What changed

• Move Inline Pesty previews into a separate floating panel anchored to the selected clip, so the Pesty bar remains at its normal height.
• Give the preview a clean document-style header, canvas, metadata footer, pointer, and spring entrance animation.
• Present Finder-copied image files as images throughout the UI and Quick Look, while preserving their original file-paste behavior.
• Keep rich link previews with favicon/title metadata and an Open in Safari action.

Why

The first inline-preview implementation resized and rendered inside the Pesty bar, which made the quick view feel like part of the strip rather than an independent preview. The floating panel gives the preview its own visual space and keeps navigation stable.

Validation

• swift build -c release --arch arm64 --arch x86_64
• swift build -c release --arch arm64 --arch x86_64 -Xswiftc -DMAS
• Packaged and tested locally on Apple Silicon.
• Intel hardware testing was not available; the x86_64 build completed successfully.

Screenshots

Demo mode; Pesty window only.