refactor: add SessionPageHeader and apply to all 6 session detail pages

- Create SessionPageHeader component (breadcrumb + editable title + collaborator + badges + date)
- Embed UPDATE_FN map internally, keyed by workshopType — no prop drilling
- Replace duplicated header blocks in sessions, motivators, year-review, weather, weekly-checkin, gif-mood

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/motivators/[id]/page.tsx

@@ -1,13 +1,10 @@
 import { notFound } from 'next/navigation';
-import Link from 'next/link';
 import { auth } from '@/lib/auth';
-import { getWorkshop, getSessionsTabUrl } from '@/lib/workshops';
 import { getMotivatorSessionById } from '@/services/moving-motivators';
 import { getUserTeams } from '@/services/teams';
 import type { ResolvedCollaborator } from '@/services/auth';
 import { MotivatorBoard, MotivatorLiveWrapper } from '@/components/moving-motivators';
-import { Badge, CollaboratorDisplay } from '@/components/ui';
-import { EditableMotivatorTitle } from '@/components/ui';
+import { Badge, SessionPageHeader } from '@/components/ui';
 
 interface MotivatorSessionPageProps {
   params: Promise<{ id: string }>;
@@ -32,50 +29,21 @@ export default async function MotivatorSessionPage({ params }: MotivatorSessionP
 
   return (
     <main className="mx-auto max-w-7xl px-4">
-      {/* Header */}
-      <div className="mb-8">
-        <div className="flex items-center gap-2 text-sm text-muted mb-2">
-          <Link href={getSessionsTabUrl('motivators')} className="hover:text-foreground">
-            {getWorkshop('motivators').label}
-          </Link>
-          <span>/</span>
-          <span className="text-foreground">{session.title}</span>
-          {!session.isOwner && (
-            <Badge variant="accent" className="ml-2">
-              Partagé par {session.user.name || session.user.email}
-            </Badge>
-          )}
-        </div>
-
-        <div className="flex items-start justify-between">
-          <div>
-            <EditableMotivatorTitle
-              sessionId={session.id}
-              initialTitle={session.title}
-              canEdit={session.canEdit}
-            />
-            <div className="mt-2">
-              <CollaboratorDisplay
-                collaborator={session.resolvedParticipant as ResolvedCollaborator}
-                size="lg"
-                showEmail
-              />
-            </div>
-          </div>
-          <div className="flex items-center gap-3">
-            <Badge variant="primary">
-              {session.cards.filter((c) => c.influence !== 0).length} / 10 évalués
-            </Badge>
-            <span className="text-sm text-muted">
-              {new Date(session.date).toLocaleDateString('fr-FR', {
-                day: 'numeric',
-                month: 'long',
-                year: 'numeric',
-              })}
-            </span>
-          </div>
-        </div>
-      </div>
+      <SessionPageHeader
+        workshopType="motivators"
+        sessionId={session.id}
+        sessionTitle={session.title}
+        isOwner={session.isOwner}
+        canEdit={session.canEdit}
+        ownerUser={session.user}
+        date={session.date}
+        collaborator={session.resolvedParticipant as ResolvedCollaborator}
+        badges={
+          <Badge variant="primary">
+            {session.cards.filter((c) => c.influence !== 0).length} / 10 évalués
+          </Badge>
+        }
+      />
 
       {/* Live Wrapper + Board */}
       <MotivatorLiveWrapper