fix(runtime): stop/restart d'agent visible robuste — kill réel, état stopped, relance froide (#196, QA verte)

Solidifie le cycle stop/restart d'un agent visible en cellule:

- terminal/registry: kill effectif de la TUI native et de la CLI custom, arrêt idempotent du live runtime (PTY + structuré), distinction nette « agent stoppé » vs « pas de session ».

- workstate + lifecycle: projection d'un état runtime explicite « stopped » (AgentRuntimeState: running/stopping/stopped/failedStart), réconcilié avec le live state; traitement des courses « agent not found ».

- relance froide via freshStart: repart de zéro sans réattacher une session morte et recharge la configuration courante de l'agent (y compris changement de modèle).

- contrat projeté côté adapters frontend (ports/domain/normalization/mock) pour la consommation UI future (#197/#198), sans surface UI ici.

Tests QA verts: workstate_actions, orchestrator_service stop_agent, agent_lifecycle (reopen/fresh_start), workstate stopped runtime state, vitest adapter stop_live_agent.

frontend/src/adapters/workStateNormalization.ts

@@ -150,11 +150,19 @@ function normalizeAgent(value: unknown, index: number): AgentWorkState {
   const agent = isRecord(value) ? value : {};
   const liveKind: "pty" | "structured" =
     isRecord(agent.live) && agent.live.kind === "structured" ? "structured" : "pty";
+  const runtimeState = normalizeRuntimeState(agent.runtimeState ?? agent.runtime_state);
   const live = isRecord(agent.live)
     ? {
         nodeId: stringValue(agent.live.nodeId),
         sessionId: stringValue(agent.live.sessionId),
         kind: liveKind,
+        ...(normalizeRuntimeState(agent.live.runtimeState ?? agent.live.runtime_state)
+          ? {
+              runtimeState: normalizeRuntimeState(
+                agent.live.runtimeState ?? agent.live.runtime_state,
+              ),
+            }
+          : {}),
       }
     : undefined;
 
@@ -173,6 +181,7 @@ function normalizeAgent(value: unknown, index: number): AgentWorkState {
     name: stringValue(agent.name, "Unnamed agent"),
     profileId: stringValue(agent.profileId, "unknown"),
     ...(live ? { live } : {}),
+    ...(runtimeState ? { runtimeState } : {}),
     busy: normalizeBusy(agent.busy),
     tickets: arrayValue(agent.tickets).map(normalizeTicket),
     inboxDepth: numberValue(agent.inboxDepth, inbox.length),
@@ -181,6 +190,18 @@ function normalizeAgent(value: unknown, index: number): AgentWorkState {
   };
 }
 
+function normalizeRuntimeState(value: unknown): AgentWorkState["runtimeState"] {
+  if (
+    value === "running" ||
+    value === "stopping" ||
+    value === "stopped" ||
+    value === "failedStart"
+  ) {
+    return value;
+  }
+  return undefined;
+}
+
 function normalizeSummaryStatus(value: unknown): ConversationPreviewStatus {
   if (
     value === "ready" ||