fix: keep consecutive requests running and clear finished stop state

Wait for OpenCode session cancellation before reusing a conversation, and replace the session after unconfirmed cancellation. Preserve terminal message state when stale streaming snapshots arrive so finished conversations return to Send.

Validated with full production Electron UI and the configured real text model: queued requests complete, cancellation followed by immediate resend completes, and Stop clears. Focused tests: 362 passed; typecheck and targeted lint passed. Live dispatch counting limitations are recorded in the feature evidence.

Release note: Consecutive OpenCode requests no longer inherit a previous cancellation, and finished conversations no longer retain the Stop button after stale updates.

src/main/agent/opencode-runtime.ts

@@ -2378,13 +2378,26 @@ export class OpenCodeRuntime implements AgentRuntime {
         AbortSignal.any([signal, subscriptionController.signal]),
       );
 
+      let sessionAbort: Promise<void> | undefined;
       const abortSession = (): void => {
-        void client.session
-          .abort({
-            sessionID: sessionId,
-            directory,
+        sessionAbort ??= this.controlRequest(
+          "取消会话",
+          (controlSignal) => client.session.abort(
+            { sessionID: sessionId, directory },
+            { signal: controlSignal },
+          ),
+        )
+          .then((response) => {
+            if (response.error || response.data !== true) {
+              throw new Error("OpenCode 会话取消失败");
+            }
           })
-          .catch(() => undefined);
+          .catch(() => {
+            // An unconfirmed abort must never target a reused session.
+            if (this.sessions.get(request.conversationId)?.id === sessionId) {
+              this.sessions.delete(request.conversationId);
+            }
+          });
       };
       signal.addEventListener("abort", abortSession, { once: true });
 
@@ -2994,6 +3007,8 @@ export class OpenCodeRuntime implements AgentRuntime {
         throw error;
       } finally {
         signal.removeEventListener("abort", abortSession);
+        // Keep the conversation locked until its session-wide abort settles.
+        await sessionAbort;
         for (const questionId of reportedQuestionIds.values()) {
           this.pendingQuestions.delete(questionId);
         }