feat(storybook): add shared SW notice and refine SW previews

- Add StoryNotice and a withSWNotice decorator so every visible SW Story
  shows the common notice above its title; non-SW Stories are unaffected.
- Align the SW Header overview with the common SW Story page layout, let the
  preview Stage fill the available width and keep inner scroll on narrow screens.
- Rename SW/Footer to SW/하단 명령어바 (sidebar title only, Story IDs fixed via
  id: "sw-footer"), drop the top SWHeader from its preview and lower the
  workspace height bounds by the removed 49px.

src/sw/sw-header-overview.tsx

@@ -69,8 +69,10 @@ export function SWHeaderOverview({ initial, fixtures, propertyGroups, propertyFi
     if (!slot) return
     const measure = () => {
       const bounds = slot.getBoundingClientRect()
-      const width = Math.max(0, Math.min(bounds.width, bounds.height * 16 / 9))
-      setSize(previous => previous.width === width ? previous : { width, height: width * 9 / 16 })
+      // 2026-11-09: the Stage height is still the 16:9 height of the fitted area (unchanged); the width now fills the slot.
+      const height = Math.max(0, Math.min(bounds.width, bounds.height * 16 / 9)) * 9 / 16
+      const width = Math.max(0, bounds.width)
+      setSize(previous => previous.width === width && previous.height === height ? previous : { width, height })
     }
     measure()
     const observer = new ResizeObserver(measure)
@@ -150,7 +152,7 @@ export function SWHeaderOverview({ initial, fixtures, propertyGroups, propertyFi
       </div></details>
     </div>}
     <div ref={slotRef} className="sw-overview-slot" data-preview-slot="">
-      <div className="sw-overview-stage" data-preview-stage="" role="region" tabIndex={0} aria-label="SW Header 16:9 미리보기, 작은 화면에서는 내부 스크롤"
+      <div className="sw-overview-stage" data-preview-stage="" role="region" tabIndex={0} aria-label="SW Header 미리보기, 작은 화면에서는 내부 스크롤"
         style={{ ...size, "--sw-preview-stage-height": `${size.height}px`, "--sw-preview-panel-left": `${panelLeft}px`, "--sw-preview-panel-top": barOpen ? "77px" : "49px" } as CSSProperties}>
         <div className="sw-overview-world">
           <SWHeader ref={headerRef} {...initial}