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.

docs/features/assistant-workbar/progress.md

@@ -1,5 +1,47 @@
 # 工作栏实现与验证进度
 
+## 2026-09-17 连续请求取消与停止状态
+
+- 复现并修复 OpenCode 迟到的会话取消中断下一条请求：同一次运行复用一个有界 abort，
+  等待取消结束后释放会话锁；取消失败时移除对应绑定。规则见
+  [本机 OpenCode](./runtime-process-reuse-technical-design.md#4-本机-opencode)。
+- 复现并修复旧 streaming 快照覆盖本地终态后停止按钮残留。完成、取消两种回归在
+  修复前失败，修复后通过；连续两条消息结束后按钮恢复。规则见
+  [消息底部请求状态](./runtime-interactions.md#消息底部请求状态)。
+- App 257 项测试通过；最终 OpenCode Runtime、权限与真实 lifecycle 105 项通过。
+  lifecycle 使用真实 OpenCode 二进制与 SDK、本地模型 fixture，验证延迟取消后同会话
+  下一条正常完成及 SSE 回收。该轮外部真实模型调用 0 次；后续完整 App 实测见下文。
+- `npm test`：4454 项通过、67 项跳过、2 项失败；失败均为 heartbeat 迁移的
+  `duplicate column name: pinned`。`npm run typecheck`、修改文件定向 ESLint、
+  `git diff --check` 通过；全库 lint 因范围外 `docs/features/story-graph/demo.js`
+  的 22 项 `document` 未定义错误失败。
+- 托管 SSH 经 `ManagedRemoteAcpRuntime` / `AgentOwnedAcpPrompt` 使用独立 ACP
+  取消流程，不复用此 HTTP abort 实现；本次未改 Agent 或远程协议，未做共享 Host 实测。
+
+### Real-model follow-up
+
+Current-source production Main, Preload, and Renderer were built into dedicated
+temporary output and launched in an isolated Electron profile on Windows. Native
+input submitted two queued OpenCode Ask requests, then cancelled another request
+after external HTTP dispatch and clicked resend within 25 ms. Both queued answers
+and the resend completed and were persisted. The cancellation was also persisted.
+After each scenario, the real DOM had no Stop button; Send was enabled after
+entering an unsent readiness probe. Both terminal screenshots were reviewed.
+
+The instrumented run dispatched exactly four external text-model HTTP requests:
+three returned HTTP 200 and one was cancelled before response headers. There were
+no observed retries or tool executions. A transparent Main relay forwarded to the
+unchanged configured HTTP upstream to count child-process requests; model answers
+and events were not simulated. An initial driver attempt completed two additional
+real generations before its counting hook was found not to cover child traffic.
+The total external dispatch count across both attempts is therefore unknown.
+
+This verifies the observed full-App flows, not deterministic stale-event ordering,
+remote Hosts, or restart behavior. Isolated credentials, profile, build, and owned
+processes were cleaned up; original settings and target source hashes were unchanged.
+The follow-up focused suite passed all 362 tests, and `npm run typecheck` passed.
+Redacted evidence: [real-model report](./consecutive-requests-live-2026-09-17.json).
+
 ## 2026-09-15 Managed browser popups
 
 Implemented [page-created tabs](./browser-tabs-technical-design.md#62-page-created-tabs): native