fix(web): address the second review round on context provenance

- An empty replacement catalog is a real catalog: `renderCatalogUpdate()`
  publishes zero entries when the last skill disappears, and falling back
  would hide that every earlier name was retired.
- The opaque fallback keeps a `form` declaration this version cannot present.
  It is the one place a newer or foreign log's declared shape would otherwise
  vanish from the UI entirely, since the row marker is also absent there.
- An instruction change with an unrecognized `action` disqualifies the record.
  The action decides the word the row shows, so an unknown one would be
  presented as loaded or updated.
- The catalog list bounds itself and reports the withheld count. Entry count
  is unbounded and the scrollport bounds height, not node count.
- A catalog message keeps content blocks this version does not know, instead
  of dropping model-visible content the extensible union may carry.
- `core.md` defines `ContextFormed`, the interface actually carrying the
  optional field, beside `ContextForm`.
- The superseded-in-part bullet states the affected clauses as one rule rather
  than enumerating them; two rounds of enumeration each missed some, which is
  the shape being fragile rather than the list being wrong.
- The note records the one migration case that does not self-heal: an
  old-format catalog as the only one, with an empty current view, leaves a
  stale catalog nothing replaces.

.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: 9dc87cd69f5d274ba5e8d66c30805cada7f1fa1a
-2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.zh.md: e650b660efe0bf308a4b1a8c72e9c89a133ac769
+2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md: dfd79a1b1b44778275b4326cf5f51f6e69ce2a7c
+2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.zh.md: 9b470dda8de45ca754a04900ffac0535ebfabd96

.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 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.
+- **Superseded in part.** Every clause below about the steer ENTRY, the `queue`/`steer` mode union, the interjection caption, its locale strings, and the goldens that pinned their absence no longer describes master — in the Decision that is bullets 1 and 3 through 5, and in the consequences bullets 1 and 3. Composer steering shipped afterwards, and 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. What still holds: host steering ownership, `ConversationService.send`'s queue-only contract, and the rejection of hiding `steering/message` from the transcript.
 - 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。
+- **部分被取代。** 下文中所有关于 steer **入口**、`queue`／`steer` mode 联合类型、插话标注、其 locale 字符串、以及钉住这些「不存在」的黄金基线的子句，均已不再描述 master——在 Decision 中是第 1 条与第 3 至 5 条，在后果中是第 1 条与第 3 条。composer steering 在此之后落地，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。仍然成立的是：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。
 - 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。