refresh_server_info

Replace the displayed server list; typically after server startup.

Rebuilds the modal body in place so a user who opened /mcp before tools finished loading sees them appear without closing/reopening. Also used by the in-place disable toggle so the cursor lands back on the same server header after F2.

The active filter is cleared on refresh: the connecting placeholder suppresses the filter input, so _query cannot be non-empty when this is called. Resetting it also prevents the programmatic Input(value=...) mount in _mount_body from triggering a redundant Input.Changed repopulation.

This is async because body.remove_children() must complete before _mount_body re-inserts an Input(id="mcp-filter") — Textual defers child removal, so a non-awaited remove leaves the old widget attached and the mount raises DuplicateIds.