fix(ui): Lot A #151 #158 #159 (QA verte)

- #151: chevauchement des boutons dans la barre supérieure pendant une conversation agent

- #158: popup de reprise de conversation intempestive (ajout cellule / changement layout / projet)

- #159: pastille d'activité de projet

frontend/src/features/projects/ProjectsView.tsx

@@ -70,6 +70,7 @@ import {
 } from "@/shared";
 import { useGateways } from "@/app/di";
 import { useProjects } from "./useProjects";
+import { useProjectActivity } from "./useProjectActivity";
 import { ProjectTabs } from "./ProjectTabs";
 import { ViewPanelBody, type ViewPanelId } from "./ViewPanelBody";
 import {
@@ -201,6 +202,7 @@ function rendezvousToastStateLabel(state: string): string {
 
 export function ProjectsView() {
   const vm = useProjects();
+  const projectActivity = useProjectActivity(vm.openTabs.map((tab) => tab.id));
   const {
     system,
     window: windowGateway,
@@ -859,6 +861,7 @@ export function ProjectsView() {
         activeTabId={vm.activeTabId}
         onSelect={(id) => vm.activateTab(id)}
         onClose={(id) => void vm.closeTab(id)}
+        activityByProjectId={projectActivity}
         projectsPanelOpen={placementOf(placements, "projects") !== "closed"}
         onOpenProjectsPanel={() => {
           setSettingsSection(null);