doc(tui): record rebuild cost, replay fixture, and the A2 fold interaction

Review follow-ups on b9b2e593f, all documentation precision. The redundancy note on `isCompactCheckpoint` leaned on a reading its call site does not state: `index.ts` reaches it for surface-eligible non-append events, which is the same set as replacements only because the marker is mandatory. Say that instead. The Agent Note now owns three facts it was leaving to a future reader. `rebuildTranscript` materializes a component per append-origin event and runs on mount, color-scheme change, and every reasoning toggle — work compaction used to bound for exactly the long sessions it serves, so the cost now tracks session length rather than the surface. `Consequences` names `surface-replayed-compaction` as the durable evidence for the live/replay equivalence claim, so the two fixtures that must move together are findable from the Note rather than the PR thread. `Deferred` records that a page can now carry a checkpoint whose `surfaceOp.start` fell out of the window: pagination no longer cuts on the checkpoint's provenance group, `FoldAdapter` pads with a non-surface sentinel, and `nodes()` degrades to `degradedSeqs()` — which is already close to the transcript projection A2 should build deliberately. Also corrects the definite-assignment comment in the snapshot scenario: the assertion rests on the awaited setup invoking `beforeMount`, not on that call being synchronous.
2026-07-29 17:43:05 +08:00
parent 035a99f922
commit b7bb4842df
5 changed files with 23 additions and 9 deletions
@@ -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/bug-fix/2026-07-29-human-transcript-append-origin.md
-2026-07-29-human-transcript-append-origin.md: c4b00dd7093ab1501a83011cf37c9841b15ce1a9
-2026-07-29-human-transcript-append-origin.zh.md: 783baaf47c137d1617c3a983c0a7bb2fa7bc50bb
+2026-07-29-human-transcript-append-origin.md: 615bec584053bdb775afbe6ad8f726132d75d6c1
+2026-07-29-human-transcript-append-origin.zh.md: d6559f2f08b730f5c7e9550cf5555c36ececd3af
@@ -24,7 +24,9 @@ No persisted event, RPC envelope, compaction transaction, or model-visible surfa

 ## Deferred

-The browser client still builds its conversation from the model surface through `FoldAdapter`, so compaction still collapses web history to a single context row. The same predicate is the fix there, together with an append-order transcript projection and a marker component; that work is a separate change against `packages/client/runtime` and `packages/client/ui-conversation`. Rendering compaction *progress* — a terminal indicator while a compaction runs — needs the bracket-first ordering that the queued manual `/compact` work introduces, and is likewise out of scope here.
+The browser client still builds its conversation from the model surface through `FoldAdapter`, so compaction still collapses web history to a single context row. The same predicate is the fix there, together with an append-order transcript projection and a marker component; that work is a separate change against `packages/client/runtime` and `packages/client/ui-conversation`.
+
+That work must handle a page whose checkpoint cites a `surfaceOp.start` outside the window: pagination no longer spends quota on the checkpoint, so it never cuts on the checkpoint's provenance group, and `FoldAdapter` pads absent events with a non-surface sentinel — so `SurfaceManager` rejects the range and `nodes()` falls back to `degradedSeqs()` with a logged error. The hole predates this change (counting could already run past a checkpoint into the range it shadows), but the old rule accidentally covered the case where the checkpoint was the oldest counted message and pulled the whole shadowed range onto its page. `degradedSeqs()` — every surface-eligible event in append order — is already close to the transcript projection A2 needs, which is the shape to build deliberately rather than reach as a degradation. Rendering compaction *progress* — a terminal indicator while a compaction runs — needs the bracket-first ordering that the queued manual `/compact` work introduces, and is likewise out of scope here.

 ## Alternatives considered

@@ -42,6 +44,10 @@ The browser client still builds its conversation from the model surface through

 Compaction no longer erases terminal history; a session compacted several times shows one marker per landed compaction, in log order. Pagination pages can carry more raw events than before, because quota is spent only on messages a human or model actually produced.

+`rebuildTranscript` now materializes a component per append-origin event in the whole log, and it runs on mount, on a terminal color-scheme change, and on every reasoning toggle. Compaction used to bound that work for exactly the long sessions compaction serves, so the cost now grows with session length instead of with the surface. That is the trade the fix exists to make — preserved history is the point — but a windowing or reuse strategy belongs to whoever first measures a slow rebuild, not to a later profiler wondering why the work grew.
+
 `dsh-tui` gains a dependency on the `dsh-compact` seam for one pure predicate, mirroring `dsh-session-reference`'s existing use. The terminal still needs no compaction backend at runtime.

 Two behaviors changed with their tests. The surface-replacement terminal test previously pinned erasure ("hides shadowed tool calls") and now pins preservation plus exactly one marker, including a pruned result copy, a regenerated assistant message, and a foreign plugin's replacement all rendering nothing. The compaction snapshot scenario wrote a `workspace-context` source while claiming to pin compaction; it now writes a real checkpoint source, and its three fixtures are re-recorded to show the preserved prompt, the full tool card, and the marker.
+
+The live/replay equivalence above is fixture-pinned, not only asserted here: `surface-replayed-compaction` mounts with the replacement already stored and records byte-identical to the live path's `surface-after-compaction-wide`. Changing either path breaks that equality, which is the point — the resume projection is what regressed for users, and the two fixtures must move together.
@@ -24,7 +24,9 @@ Status: implemented

 ## Deferred

-浏览器客户端仍通过 `FoldAdapter` 从模型 surface 构建会话，因此压缩在 Web 端仍会把历史折叠成一行上下文。那里的修复用的是同一个谓词，另需按追加顺序的记录投影与一个标记组件；该工作是针对 `packages/client/runtime` 与 `packages/client/ui-conversation` 的独立变更。渲染压缩*进度*——压缩运行期间的终端指示——需要排队式手动 `/compact` 工作引入的“先开括号”顺序，同样不在本次范围内。
+浏览器客户端仍通过 `FoldAdapter` 从模型 surface 构建会话，因此压缩在 Web 端仍会把历史折叠成一行上下文。那里的修复用的是同一个谓词，另需按追加顺序的记录投影与一个标记组件；该工作是针对 `packages/client/runtime` 与 `packages/client/ui-conversation` 的独立变更。
+
+该工作必须处理这样一页：其检查点引用的 `surfaceOp.start` 落在窗口之外。分页不再为检查点消耗额度，因此永远不会按检查点的溯源分组切分；而 `FoldAdapter` 会用一个非 surface 的哨兵事件填补缺失事件——于是 `SurfaceManager` 拒绝该范围，`nodes()` 退化为 `degradedSeqs()` 并记录一条错误。这个缺口早于本次变更（此前计数就可能越过检查点进入它所遮蔽的范围），但旧规则恰好覆盖了这样一种情形：检查点是最旧的被计数消息，其溯源分组把整段被遮蔽的范围一起拉到该页。`degradedSeqs()`——按追加顺序的每个 surface 可入事件——已经很接近 A2 所需的记录投影，因此那正是应当刻意构建的形态，而不是作为退化路径被动落到的结果。渲染压缩*进度*——压缩运行期间的终端指示——需要排队式手动 `/compact` 工作引入的“先开括号”顺序，同样不在本次范围内。

 ## Alternatives considered

@@ -42,6 +44,10 @@ Status: implemented

 压缩不再抹掉终端历史；被压缩多次的会话会按日志顺序显示每次落地压缩对应的一行标记。分页的每一页可以携带比以前更多的原始事件，因为额度只花在人类或模型真正产生的消息上。

+`rebuildTranscript` 现在会为整份日志中的每个追加来源事件物化一个组件，并在挂载时、终端配色方案变化时以及每次切换 reasoning 时运行。压缩此前正好为压缩所服务的那些长会话限制了这项工作量，因此这份开销现在随会话长度增长，而不再随 surface 增长。这正是本次修复要做的取舍——保留历史才是目的——但窗口化或复用策略属于第一个真正测到重建变慢的人，而不属于日后某个疑惑工作量为何增长的性能分析者。
+
 `dsh-tui` 为一个纯谓词新增了对 `dsh-compact` 接缝的依赖，与 `dsh-session-reference` 现有用法一致。终端在运行时仍然不需要任何压缩后端。

 两项行为随其测试一起改变。表层替换的终端测试此前钉住的是抹除（“隐藏被遮蔽的工具调用”），现在钉住的是保留加恰好一行标记，其中被裁剪的结果副本、重新生成的 assistant 消息以及来自其他插件的替换都不渲染任何内容。压缩快照场景此前声称钉住压缩，却写入了 `workspace-context` 来源；现在它写入真实的检查点来源，并重新录制三份 fixture，以显示被保留的提示、完整的工具卡片和那行标记。
+
+上文的实时／回放等价性由 fixture 钉住，而不只是在此断言：`surface-replayed-compaction` 在挂载时替换已经存在，其录制结果与实时路径的 `surface-after-compaction-wide` 逐字节一致。改动任一路径都会破坏这项相等——这正是要点：回放投影才是当初对用户造成回归的部分，两份 fixture 必须一起变动。
@@ -110,9 +110,11 @@ export function transcriptToolCallIds(session: Session): Set<string> {
 * `tool/result`, a regenerated `assistant/message`) rewrite one node for the
 * model and mark no boundary in the conversation.
 *
- * The replacement check is redundant at both current call sites, which already
- * reached a replacement: it keeps the exported predicate true to its name for a
- * third caller, rather than making that caller repeat the check.
+ * The replacement check is redundant at both current call sites, because a
+ * surface-eligible non-append event is a replacement: the marker is mandatory,
+ * so `Session.append` and the replay fold reject an event that carries none.
+ * The check keeps the exported predicate true to its name for a third caller,
+ * rather than making that caller repeat it.
 * @param event - event to test.
 * @returns true when the event compacted a surface range.
 */
@@ -749,8 +749,8 @@ describe('TUI terminal-state snapshots', () => {
    // real-clock millisecond tick between the fixture appends and the render
    // would flip `Tools 0.0s` in and out of the pinned header.
    const nowSpy = vi.spyOn(Date, 'now').mockReturnValue(COMPACTION_FIXTURE_TIME)
-    // beforeMount runs synchronously inside setupSnapshot, so the range the
-    // checkpoint replaces is assigned before the first await below.
+    // The awaited setup always invokes beforeMount, so the range the checkpoint
+    // replaces is assigned by the time the appends below need it.
    let compacted!: CompactionRange
    const harness = await setupSnapshot({
      tools: ADVANCED_CARD_TOOLS,