feat(session-limits): LS7-front — UI limites de session (badge + compte à rebours + filet humain)

Expose la surface produit des limites de session côté React/TS,
au-dessus du câblage backend (9df5923).

- domain/index.ts : 5 variantes ajoutées au union DomainEvent
  (agentRateLimited / ResumeScheduled / ResumeCancelled / Resumed /
  RateLimitSuspected).
- ports/index.ts : cancelResume(agentId) ajouté à InputGateway.
- adapters/input.ts : TauriInputGateway.cancelResume → invoke("cancel_resume").
- adapters/mock/index.ts : MockInputGateway.cancelResume
  (cancelledResumes / cancelResumeResult).
- features/agents/useAgents.ts : état limitByAgent + action cancelResume.
- features/agents/AgentLimitBadge.tsx (nouveau) : badge + compte à rebours
  + bouton Annuler + helpers purs.
- features/agents/AgentsPanel.tsx : câblage du badge.

Tests : useAgentsLimits.test.tsx (13) + AgentLimitBadge.test.tsx (11),
suite agents 63 tests verts, tsc --noEmit propre.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/features/agents/AgentsPanel.tsx

@@ -21,6 +21,7 @@ import { TerminalView } from "@/features/terminals/TerminalView";
 import { useDrift } from "@/features/templates/useDrift";
 import { useGateways } from "@/app/di";
 import { useAgents } from "./useAgents";
+import { AgentLimitBadge } from "./AgentLimitBadge";
 
 export interface AgentsPanelProps {
   /** The project whose agents to manage. */
@@ -327,6 +328,8 @@ export function AgentsPanel({ projectId, projectRoot = "" }: AgentsPanelProps) {
               // Source of this agent's last orchestration delegation (mcp vs
               // file), if any has been observed. Absent ⇒ no badge.
               const delegationSource = vm.delegationSourceByRequester[a.id];
+              // Session-limit state (ARCHITECTURE §21), if the agent is limited.
+              const limitState = vm.limitByAgent[a.id];
               return (
                 <li
                   key={a.id}
@@ -373,6 +376,14 @@ export function AgentsPanel({ projectId, projectRoot = "" }: AgentsPanelProps) {
                     )}
                   </button>
 
+                  {limitState && (
+                    <AgentLimitBadge
+                      state={limitState}
+                      busy={vm.busy}
+                      onCancelResume={() => void vm.cancelResume(a.id)}
+                    />
+                  )}
+
                   <div className="flex flex-wrap items-center gap-1.5">
                     {/* Profile hot-swap selector (Chantier A). Changing the
                         engine abandons the conversation history → confirmation. */}