feat(web): state the run state on the terminal card's prompt line

The terminal card showed no run state: a running command and a settled
command that produced no output rendered the same prompt line, so whether
a command was still running had to be inferred from the absence of output.

Lead the prompt line with a StateDot in three of its states — the spinning
ring while running, red for the same exit status that renders the status
pill, green for a clean settle. That is the same indicator a tool row's
leading icon carries, so a row and its own card cannot disagree about one
command; the row/card agreement is pinned in the ui-conversation spec.
StateDot is aria-hidden, so a visually hidden text label rides beside it,
which is what the refreshed aria goldens now record.

The e2e adds what jsdom cannot compute: the dot's color resolves to the
green success token through the real theme stylesheet, and the dot precedes
the prompt label in document order.

packages/client/ui-primitives/src/StateDot.tsx

@@ -19,8 +19,8 @@ export type StateDotState = 'done' | 'warning' | 'ongoing' | 'error'
  */
 export function StateDot({ state, size = 10, className }: {
   state: StateDotState
-  size?: number
-  className?: string
+  size?: number | undefined
+  className?: string | undefined
 }) {
   const gradientId = useId()
   if (state === 'ongoing') {