feat: redesign agents page (architectural-grid style), add image description, fix AI limits, remove dead code

- Redesign agents page with architectural-grid (8) design system:
  rounded-2xl cards, serif headings, motion tabs, dashed templates section
- Replace agent form popup with full-page detail view (SettingsView style)
  with dark planning card, section tooltips, and help button
- Hide advanced mode for slide/excalidraw generators
- Add 'describe images' action to contextual AI assistant
- Add copy button to action/resource preview with HTTP fallback
- Add delete history button to agent run log panel
- Increase AI word limit from 2000 to 5000 (reformulate + transform-markdown)
- Increase max steps slider from 25 to 50
- Fix image description error with clear model compatibility message
- Fix doubled execution count display in agent detail view
- Remove dead files: notes-list-view.tsx, notes-view-toggle.tsx
- Remove 'list' view mode from NotesViewMode type
- Add missing i18n keys (back, configuration, options, copy, cleared)

memento-note/app/actions/agent-actions.ts

@@ -287,6 +287,31 @@ export async function getAgentActions(agentId: string) {
   }
 }
 
+export async function deleteAgentHistory(agentId: string) {
+  const session = await auth()
+  if (!session?.user?.id) {
+    throw new Error('Non autorise')
+  }
+
+  try {
+    const agent = await prisma.agent.findFirst({
+      where: { id: agentId, userId: session.user.id },
+      select: { id: true }
+    })
+    if (!agent) throw new Error('Agent non trouve')
+
+    await prisma.agentAction.deleteMany({
+      where: { agentId }
+    })
+
+    revalidatePath('/agents')
+    return { success: true }
+  } catch (error) {
+    console.error('Error deleting agent history:', error)
+    throw new Error('Impossible de supprimer l\'historique')
+  }
+}
+
 export async function toggleAgent(id: string, isEnabled: boolean) {
   const session = await auth()
   if (!session?.user?.id) {