fix(domain,application,infrastructure,backend,app-tauri,frontend): Stop demande agent préserve la conversation ouverte — arrêt sans fermeture/clôture du chat, états cohérents après cancel sur les 3 adapters de session, cellule et workstate synchronisés — #343 (QA verte)

frontend/src/adapters/agent.test.ts

@@ -226,7 +226,15 @@ describe("TauriAgentGateway invoke payloads", () => {
   });
 
   it("cancelAgentChat invokes cancel_agent_chat without closing the session", async () => {
-    await new TauriAgentGateway().cancelAgentChat("chat-session-1");
+    const response = {
+      sessionId: "chat-session-1",
+      outcome: "cancelled" as const,
+    };
+    invoke.mockResolvedValueOnce(response);
+
+    await expect(
+      new TauriAgentGateway().cancelAgentChat("chat-session-1"),
+    ).resolves.toEqual(response);
 
     expect(invoke).toHaveBeenCalledWith("cancel_agent_chat", {
       sessionId: "chat-session-1",

frontend/src/adapters/agent.ts

@@ -17,6 +17,7 @@ import { Channel, invoke } from "@tauri-apps/api/core";
 import type {
   Agent,
   AgentContextDocument,
+  CancelAgentChatResult,
   EffortSelection,
   GatewayError,
   ExecuteSlashCommandResult,
@@ -364,8 +365,8 @@ export class TauriAgentGateway implements AgentGateway {
     await invoke("close_agent_session", { sessionId });
   }
 
-  async cancelAgentChat(sessionId: string): Promise<void> {
-    await invoke("cancel_agent_chat", { sessionId });
+  async cancelAgentChat(sessionId: string): Promise<CancelAgentChatResult> {
+    return invoke<CancelAgentChatResult>("cancel_agent_chat", { sessionId });
   }
 
   async reattach(

frontend/src/adapters/http/agentGateway.test.ts

@@ -308,11 +308,16 @@ describe("HttpAgentGateway WS round-trip (B6 frames)", () => {
         baseUrl: "https://host",
         fetchImpl: async (url, init) => {
           calls.push({ url, init });
+          const command = JSON.parse((init as { body: string }).body).command;
+          const response =
+            command === "cancel_agent_chat"
+              ? { sessionId: "chat-1", outcome: "cancelled" }
+              : undefined;
           return {
             ok: true,
             status: 200,
-            json: async () => undefined,
-            text: async () => "",
+            json: async () => response,
+            text: async () => response ? JSON.stringify(response) : "",
           };
         },
       }),
@@ -402,7 +407,10 @@ describe("HttpAgentGateway WS round-trip (B6 frames)", () => {
     });
     expect(chunks).toEqual([{ kind: "final", content: "Hello back" }]);
 
-    await gw.cancelAgentChat("chat-1");
+    await expect(gw.cancelAgentChat("chat-1")).resolves.toEqual({
+      sessionId: "chat-1",
+      outcome: "cancelled",
+    });
     await gw.closeAgentChat("chat-1");
     await gw.detachAgentChat("chat-1");
 

frontend/src/adapters/http/streamGateways.ts

@@ -23,6 +23,7 @@ import type {
   Agent,
   AgentContextDocument,
   AppExitWorkGuardState,
+  CancelAgentChatResult,
   DomainEvent,
   EffortSelection,
   ExecuteSlashCommandResult,
@@ -469,8 +470,8 @@ export class HttpAgentGateway implements AgentGateway {
     await this.http.invoke("close_agent_session", { sessionId });
   }
 
-  async cancelAgentChat(sessionId: string): Promise<void> {
-    await this.http.invoke("cancel_agent_chat", { sessionId });
+  async cancelAgentChat(sessionId: string): Promise<CancelAgentChatResult> {
+    return this.http.invoke<CancelAgentChatResult>("cancel_agent_chat", { sessionId });
   }
 }
 

frontend/src/adapters/mock/index.ts

@@ -9,6 +9,7 @@ import type {
   AgentDrift,
   AppExitWorkGuardState,
   AgentProfile,
+  CancelAgentChatResult,
   DiagnosticWarning,
   DomainEvent,
   EffortSelection,
@@ -1133,13 +1134,14 @@ export class MockAgentGateway implements AgentGateway {
     }
   }
 
-  async cancelAgentChat(sessionId: string): Promise<void> {
+  async cancelAgentChat(sessionId: string): Promise<CancelAgentChatResult> {
     if (!this.chatScrollback.has(sessionId)) {
       throw {
         code: "NOT_FOUND",
         message: `agent chat session ${sessionId} not found`,
       } as GatewayError;
     }
+    return { sessionId, outcome: "cancelled" };
   }
 
   async reattach(