Connection Info modal: header scrolls out of view

[cliffhall]

Follow-up to #1698. The Connection Info modal (clients/web/src/components/groups/ConnectionInfoModal/ConnectionInfoModal.tsx) has the same structure the settings modals had before #1698 — a custom header Group (title + close) inside a Stack in the modal body, with the default <Modal> and no scrollAreaComponent. So when the connection details are long enough to overflow the viewport, the whole modal scrolls and the header (title + close) scrolls out of view.

Expected

• The Connection Info header stays visible on scroll.
• Only the content area below it scrolls.

Scope

• clients/web/src/components/groups/ConnectionInfoModal/ConnectionInfoModal.tsx

Fix

Apply the same change used for the settings modals in #1698 (PR #1753): switch from the default <Modal> to the compound Modal.Root / Modal.Overlay / Modal.Content / Modal.Header / Modal.Body API, move the header row into Modal.Header, and set scrollAreaComponent={ScrollArea.Autosize}. The fade-down transition is already supplied app-wide by ThemeModalRoot (added in #1753), so no transitionProps literal is needed.

[cliffhall]

The Connection Info modal (ConnectionInfoModal.tsx) has been modified — switched to the compound Modal.Root/Header/Body API with scrollAreaComponent={ScrollArea.Autosize} so the header stays pinned while the body scrolls (same fix as #1698). Addressed in PR #1755.

Verified in Storybook (WithOAuth, short viewport); the same effect your everything-server config produces via its long instructions section. Header stays pinned when scrolled to Server Instructions / OAuth Details:

[cliffhall]

Merged via #1755 (squash into v2/main).