docs(storybook): simplify sidebar Story pages around the UI

Drop the category kicker from the 83 sidebar Stories (kicker is now optional;
hidden verification Stories keep it) and shorten or remove repeated, obvious
or internal page/section descriptions. Required specs, limits, virtual-data
and undecided-value notices stay. Story IDs, exports, fixtures, shared state
notes and package code are unchanged. Record: docs/reports/storybook-ui-simplification-2026-10-22.md

src/foundation/reference.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useRef, useState, type ReactNode } from "react"
-import { STORY_KICKER, StoryPage, StoryPageHeader, StorySection } from "@/components/story-page"
+import { StoryPage, StoryPageHeader, StorySection } from "@/components/story-page"
 import "./foundation.css"
 
 export function useResolvedProperties(properties: readonly string[]) {
@@ -25,7 +25,7 @@ export function useResolvedProperties(properties: readonly string[]) {
 
 // The page frame, title and sections are the common Story page (src/components/story-page.tsx); .hm-foundation styles the reference content.
 export function ReferencePage({ title, intro, children }: { title: string; intro: string; children: ReactNode }) {
-  return <StoryPage className="hm-foundation"><StoryPageHeader kicker={STORY_KICKER.foundation} title={title} description={intro} />{children}</StoryPage>
+  return <StoryPage className="hm-foundation"><StoryPageHeader title={title} description={intro} />{children}</StoryPage>
 }
 export function ReferenceSection({ title, note, children, id }: { title: string; note: string; children: ReactNode; id?: string }) {
   return <StorySection id={id} title={title} description={note}>{children}</StorySection>