feat: roll out illustrative empty states across 8 pages with 2 new guide entries

- TreeLibraryPage: split empty state into no-flows (illustration + CTA) vs no-filter-results
- MyAnalyticsPage/TeamAnalyticsPage: add zero-sessions empty state with illustration
- SessionHistoryPage: split into no-sessions (illustration) vs no-filter-results
- StepLibraryBrowser: illustrative empty state when no steps exist
- ScriptTemplateList: replace plain empty state with ScriptIllustration
- MySharesPage: replace icon-based empty state with ShareIllustration
- IntegrationsPage: add IntegrationIllustration above setup form
- Add script-templates and psa-setup guides to guides data
- Add EmptyState vitest tests (7 tests)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/TeamAnalyticsPage.tsx

@@ -12,6 +12,7 @@ import {
 } from 'recharts'
 import { Spinner } from '@/components/common/Spinner'
 import { EmptyState } from '@/components/common/EmptyState'
+import { AnalyticsIllustration } from '@/components/common/EmptyStateIllustrations'
 import { analyticsApi } from '@/api'
 import { usePermissions } from '@/hooks/usePermissions'
 import { toast } from '@/lib/toast'
@@ -70,6 +71,7 @@ export default function TeamAnalyticsPage() {
     return (
       <div className="container mx-auto px-4 py-6 sm:px-6 sm:py-8">
         <EmptyState
+          illustration={<AnalyticsIllustration />}
           title="Analytics unavailable"
           description="Failed to load analytics data. Please try again."
         />
@@ -77,6 +79,27 @@ export default function TeamAnalyticsPage() {
     )
   }
 
+  if (data.summary.total_sessions === 0) {
+    return (
+      <div className="container mx-auto px-4 py-6 sm:px-6 sm:py-8">
+        <EmptyState
+          illustration={<AnalyticsIllustration />}
+          title="Track your troubleshooting performance"
+          description="Analytics show resolution times, common paths, and team efficiency. Data appears automatically as you complete sessions."
+          action={
+            <Link
+              to="/trees"
+              className="inline-flex items-center gap-2 rounded-[10px] bg-gradient-brand px-5 py-2.5 text-sm font-semibold text-[#101114] shadow-lg shadow-primary/20 hover:opacity-90 active:scale-[0.97] transition-all"
+            >
+              Run Your First Session
+            </Link>
+          }
+          learnMoreLink="/guides/analytics"
+        />
+      </div>
+    )
+  }
+
   const { summary, time_series, top_flows, top_engineers } = data
 
   return (