feat(ui): add breadcrumb icons, fix alignment, and remove duplicate form headers

- add section icons to all breadcrumbs across every page
- fix breadcrumb nav display:flex so icons align vertically with buttons
- wrap all page breadcrumbs in pageToolbar div for consistent layout
- add Breadcrumbs to AllRunsPage which previously used a plain h1
- fix envCardHeader flex:1 so settings button hugs the right edge
- remove card header from environment create/edit forms (duplicated breadcrumb)

client/src/pages/scenario/ScenarioDetailPage.tsx

@@ -1,7 +1,7 @@
 import { useEffect, useState } from 'react';
 import { useNavigate, useParams } from 'react-router-dom';
 import { useTranslation } from 'react-i18next';
-import { Play, Pencil, Plus, History, Trash2, Upload, GripVertical } from 'lucide-react';
+import { Play, Pencil, Plus, History, Trash2, Upload, GripVertical, ClipboardList } from 'lucide-react';
 import { stringify as yamlStringify } from 'yaml';
 import { scenarios, steps, scenarioCredentials, credentials as credentialsApi } from '../../api';
 import type { Scenario, ScenarioStep, ScenarioCredential, Credential } from '../../api';
@@ -269,7 +269,7 @@ export function ScenarioDetailPage() {
       <div className={styles.pageToolbar}>
         <Breadcrumbs
           items={[
-            { label: t('scenarios.title'), onClick: () => navigate('/scenarios') },
+            { label: t('scenarios.title'), icon: <ClipboardList size={14} />, onClick: () => navigate('/scenarios') },
             { label: scenario?.name ?? `#${id}` },
           ]}
         />
@@ -313,7 +313,7 @@ export function ScenarioDetailPage() {
         <>
           <Card>
             <DescriptionList
-              layout="comfortable"
+              layout="grid"
               items={[
                 { term: t('scenarios.field_id'), detail: <UuidBadge id={scenario.id} /> },
                 { term: t('scenarios.field_name'), detail: scenario.name },