feat(storybook): refine Manager LNB, HM Color and Patterns/Layout/LNB

- Manager LNB: 246px width, 16px brand title, 14px/700 menu and section
  titles, depth1 48px / depth2+ 42px rows, 24px section gap
- Foundation: rename Color to HM Color (Story ID foundation-color--all kept),
  remove Company Colors subtitle and the page-title bottom border
- Patterns/Layout/LNB: Storybook-only overrides in lnb.stories.css
  (240px column, 212px min width, 14px menu, 48/42px rows, profile text,
  group dividers); representative board dividers per section
- Sync story inventory and docs (brand-color-steps, lnb); shared package
  defaults and tokens are unchanged

src/components/story-page.css

@@ -1,5 +1,5 @@
 /* Storybook presentation only. Common page frame for representative Stories; all selectors stay inside .sb-page.
-   Inner (fluid; 16px each side up to 480px, growing to 60px at 768px; vertical gutter 16–40) and title (kicker 12 / title 28·36·700 / description, underlined) reuse Foundation / Color.
+   Inner (fluid; 16px each side up to 480px, growing to 60px at 768px; vertical gutter 16–40) and title (kicker 12 / title 28·36·700 / description, no divider below) reuse Foundation / Color.
    Section reuses the Center Graphic / 교량 split: heading + description, a divider, then the specimen. */
 .sb-page {
   --sb-page-gutter: clamp(16px, 3vw, 40px);
@@ -22,7 +22,6 @@
 
 .sb-page .sb-page-header {
   padding-bottom: 24px;
-  border-bottom: 1px solid var(--hm-sem-stroke-input-default);
   font-size: var(--hm-label-font-size);
   line-height: var(--hm-label-line-height);
   overflow-wrap: anywhere;