fix(web): align the context separator with ToolRow and name the caption

Review follow-ups on the context provenance row:

- the producer name now follows ToolRow's aria-hidden separator dot instead
  of a literal middot inside the text, so the two disclosure rows expose one
  accessible-name shape;
- the English steering caption becomes the noun `Interjection`, parallel to
  the Chinese 插话 and to the label this bubble carried before;
- the history fold gets its own provenance assertion, so the mapping it
  declares separately from TranscriptAdapter is pinned on both sides;
- the superseded-in-part bullet on the no-interjection-chrome note now
  enumerates the third Decision bullet too, whose no-badge and no-IconActions
  clauses had both lapsed.

.agents/notes/implemented/simplification/2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write .agents/notes/implemented/simplification/2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md
-2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md: 15b9b9d299161e9d7404b43cfabfdc11e87d8feb
-2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.zh.md: 8c25f2700c316e75d29143e85c4c966fcb744c85
+2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md: 9dc87cd69f5d274ba5e8d66c30805cada7f1fa1a
+2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.zh.md: e650b660efe0bf308a4b1a8c72e9c89a133ac769

.agents/notes/implemented/simplification/2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md

@@ -28,7 +28,7 @@ Keep host and runtime steering intact. Remove only the Web UI entry and chrome:
 
 ## Consequences
 
-- **Superseded in part.** Composer steering shipped afterwards, so the first Decision bullet and the first consequence below no longer describe master: `InputMachine` carries the `queue`/`steer` mode union again and Web users can steer. The [context-source and steer marks decision](../feature/2026-08-04-web-context-source-and-steer-marks.md) then supplied the product decision this note's reintroduction clause required and restored the `插话` caption on steering bubbles. Host steering ownership, `ConversationService.send`'s queue-only contract, and the rejection of hiding `steering/message` from the transcript still hold.
+- **Superseded in part.** Composer steering shipped afterwards, so the first and third Decision bullets and the first consequence below no longer describe master: `InputMachine` carries the `queue`/`steer` mode union again, Web users can steer, and the steering bubble regained its user IconActions before carrying a caption again. The [context-source and steer marks decision](../feature/2026-08-04-web-context-source-and-steer-marks.md) then supplied the product decision this note's reintroduction clause required and restored the `插话` caption on steering bubbles. Host steering ownership, `ConversationService.send`'s queue-only contract, and the rejection of hiding `steering/message` from the transcript still hold.
 - Web users cannot steer from the composer or `ctx.conversation.send`; stop/cancel and Queue remain the only mid-turn controls.
 - Host-wire and non-Web clients can still steer; the Web client shows those messages without labeling them as interjections.
 - Reintroducing a dedicated steer UI would need a new product decision; do not revive the mode union or badge without one.

.agents/notes/implemented/simplification/2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.zh.md

@@ -28,7 +28,7 @@ Status: implemented
 
 ## 后果
 
-- **部分被取代。** composer steering 在此之后落地，因此 Decision 的第一条与下面的第一条后果都已不再描述 master：`InputMachine` 重新携带 `queue`／`steer` mode 联合类型，Web 用户可以 steer。随后[上下文来源与 steer 标识决策](../feature/2026-08-04-web-context-source-and-steer-marks.md)提供了本 note 重新引入条款所要求的产品决策，并恢复了 steering 气泡上的 `插话` 标注。host 侧 steering 的归属、`ConversationService.send` 仅排队的契约，以及不在 transcript 中隐藏 `steering/message` 的取舍，仍然成立。
+- **部分被取代。** composer steering 在此之后落地，因此 Decision 的第一条与第三条、以及下面的第一条后果都已不再描述 master：`InputMachine` 重新携带 `queue`／`steer` mode 联合类型，Web 用户可以 steer，steering 气泡也早在重新带上标注之前就恢复了用户 IconActions。随后[上下文来源与 steer 标识决策](../feature/2026-08-04-web-context-source-and-steer-marks.md)提供了本 note 重新引入条款所要求的产品决策，并恢复了 steering 气泡上的 `插话` 标注。host 侧 steering 的归属、`ConversationService.send` 仅排队的契约，以及不在 transcript 中隐藏 `steering/message` 的取舍，仍然成立。
 - Web 用户无法从 composer 或 `ctx.conversation.send` steer；中途控制只剩停止／取消与 Queue。
 - Host 线缆与非 Web 客户端仍可 steer；Web 客户端展示这些消息时不再标成插话。
 - 若要重新引入专用 steer UI，需要新的产品决策；没有决策就不要复活 mode 联合类型或徽章。