feat(client): localize composer hints and rework input command interaction

Unify the /plan claimed hint with the plan placeholder through a locale
namespace, localize slash menu group titles, replace the PermissionSelect
native select with the Menu primitive, add a goal pause verb chain, clamp
anchored popups to the viewport with scroll-into-view and outside-dismiss,
and fix onPasteUpgrade insertedRange to account for the chip trailing gap.

packages/client/ui-primitives/src/useAnchoredMaxHeight.ts

@@ -0,0 +1,38 @@
+/**
+ * Viewport-fit hook for bottom-anchored overlays (slash menu, popupSelect):
+ * the element's bottom edge is laid out independent of its height, so it
+ * grows upward and only the top edge can collide with the viewport — clamp
+ * the design cap to the space between that edge and the viewport top.
+ */
+import { useLayoutEffect, useState } from 'react'
+import type { RefObject } from 'react'
+
+/** Safe distance kept between the overlay and the viewport top edge (mirrors the Menu portal margin). */
+const MARGIN = 12
+
+/**
+ * Clamp a bottom-anchored overlay's max-height to the viewport.
+ * @param ref - the overlay element; a null current (overlay closed) skips measuring.
+ * @param cap - design max-height in px (the clamp never exceeds it).
+ * @param signal - re-measure trigger: pass the overlay's render state so anchor
+ *   moves (composer growth) re-fit; resize/scroll re-fit while mounted.
+ * @returns the max-height to apply inline, in px.
+ */
+export function useAnchoredMaxHeight(ref: RefObject<HTMLElement>, cap: number, signal: unknown): number {
+  const [maxHeight, setMaxHeight] = useState(cap)
+  useLayoutEffect(() => {
+    const el = ref.current
+    if (el === null) return
+    const fit = () => {
+      setMaxHeight(Math.min(cap, Math.max(0, el.getBoundingClientRect().bottom - MARGIN)))
+    }
+    fit()
+    window.addEventListener('resize', fit)
+    window.addEventListener('scroll', fit, true)
+    return () => {
+      window.removeEventListener('resize', fit)
+      window.removeEventListener('scroll', fit, true)
+    }
+  }, [ref, cap, signal])
+  return maxHeight
+}