feat(settings): open Assistenten on Kunskap with the konteringskarta first (#1044)

The Assistenten settings hub used to open on Minne, with the
konteringskarta buried two clicks away (Kunskap tab, below a second
nested tab row). Now /settings/assistant opens on Kunskap and the
LedgerGraph hero is the first thing on screen.

- Kunskap is the default view and first tab; Minne moves to ?view=memory
  (old ?view=knowledge links still resolve to the default)
- Drop the nested Kompetens/Minne/Regler & profil tab row inside the
  Kunskap view: Kompetens and Minne duplicated the top-level tabs one
  row above; Regler & profil now renders inline under the graph with a
  section header (KnowledgeTabs.tsx deleted)
- Restore vertical rhythm (space-y-8) between the hero, detail section
  and footer, lost when the view moved into the settings tabs
- Update redirects and memory deep links (/settings/agent-memory,
  AgentChat memory chips, FactsCard manage link) to ?view=memory
- Match the loading skeleton to the new layout

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

components/dashboard/DashboardNav.tsx

@@ -189,8 +189,8 @@ const navItems: NavItem[] = [
   // Rapporter surface (nav_ia_redesign §F) is built.
   { href: '/kpi', labelKey: 'kpi', icon: TrendingUp, group: 'analys' },
   { href: '/reports', labelKey: 'reports', icon: BarChart3, group: 'analys' },
-  // "Vad din agent vet" now lives inside Settings (Assistenten -> Kunskap),
-  // reachable via /settings/assistant?view=knowledge, not the top nav.
+  // "Vad din agent vet" now lives inside Settings (Assistenten -> Kunskap,
+  // the default view), reachable via /settings/assistant, not the top nav.
   // Data: master-data registers + data plumbing. Anställda is a register
   // (you edit an employee rarely, you run payroll monthly), so it lives here
   // while the Löner flow stays in Arbeta.