docs(ui-trajectory): record timeline interaction contract

.agents/notes/implemented/feature/2026-07-27-trajectory-inspection-ledger.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/feature/2026-07-27-trajectory-inspection-ledger.md
-2026-07-27-trajectory-inspection-ledger.md: 8c2a7c42b7898776de5d42459b09c0fb1737ec0b
-2026-07-27-trajectory-inspection-ledger.zh.md: 6c5733046dc2cfd3fd2bd005f4cf5c2d2bd110af
+2026-07-27-trajectory-inspection-ledger.md: fcdbbb30b065b0b128a8e375cd2e8ed5b2702dac
+2026-07-27-trajectory-inspection-ledger.zh.md: ea31389d2fb0970caae271e7d64e4ecff215e93c

.agents/notes/implemented/feature/2026-07-27-trajectory-inspection-ledger.md

@@ -21,7 +21,8 @@ Trajectory has to make prose, machine payloads, token usage, timing, and nested
 - Call schemas come from the active recorded Request header. Keyless snapshot fixtures deliberately replace that catalog with the non-array `{{tools}}` token, which the durable inspection boundary treats as unavailable instead of attempting to project or fabricate schemas.
 - Selecting a record or Request opens an inspector inside Trajectory. Tabs and Summary sections follow the selected entity: Markdown messages expose rendered, source, provenance, and hierarchy views; tools add JSON payload/result and schema views; Requests add options, usage, timing, and result navigation. Images render as media rather than serialized data.
 - Turn folding removes all rows after its first record and replaces them with a compact step/tool-call count; Assistant folding applies the same interaction to its tool-call descendants. Global controls fold or expand both levels.
-- The separate Waterfall tab is removed. A fixed Overview above the ledger projects every record with known `startedAt` onto three semantic timing lanes using its own duration. Dragging left or right commits an inclusive interval filter: any record whose active interval overlaps either boundary remains visible, records without known timing leave the focused ledger, and clearing the selection restores the full branch. The Overview keeps the full time domain while focused so the selection can be resized or cleared without losing orientation.
+- The separate Waterfall tab is removed. A fixed Overview above the ledger projects every record with known `startedAt` onto three semantic timing lanes using its own duration. Finalized Assistant spans divide the recorded interval at the first non-empty token delta, so distinct TTFT and decoding colors retain their actual ratio; incomplete timing falls back to one Assistant color. Hovering for 500 ms exposes exact start/end, total duration, TTFT, and decoding time without relying on the browser's native tooltip delay. Dragging left or right commits an inclusive interval filter: any record whose active interval overlaps either boundary remains visible, records without known timing leave the focused ledger, and clearing the selection restores the full branch. Wheel gestures zoom the time domain. A right-button click clears the interval selection; dragging instead pans an already zoomed viewport without mutating it. The Overview keeps the full time domain while focused so the selection can be resized or cleared without losing orientation.
+- Live history updates retain the ledger's bottom position only while the user is already following its tail. Scrolling upward clears that follow state, so streamed chunks and newly appended records do not interrupt inspection of earlier rows.
 - This local inspector remains independent from the conversation-wide Chat details column. At narrow widths it overlays the ledger and remains dismissible by keyboard or pointer.
 
 ## Alternatives considered
@@ -40,4 +41,4 @@ Trajectory has to make prose, machine payloads, token usage, timing, and nested
 
 ## Consequences
 
-Trajectory shows more useful records per viewport while retaining Turn and Request orientation. Context rewrites and compactions remain inline with their surrounding history, while a rewind begins a successor branch that inherits only the retained prefix. The main ledger omits token usage and duration so content receives the available width; the local inspector exposes those facts together with full payloads, provenance, schemas, and request timing. The Overview uses recorded start/duration facts without fabricating live elapsed time, and its inclusive focus behavior matches the interaction users already know from Chrome DevTools Network. Focused component tests pin projection, folding, record and interval selection, entity-specific tabs, and running/error semantics; the assembled Web snapshot pins the ledger, Overview, and inspector through the real client composition.
+Trajectory shows more useful records per viewport while retaining Turn and Request orientation. Context rewrites and compactions remain inline with their surrounding history, while a rewind begins a successor branch that inherits only the retained prefix. The main ledger omits token usage and duration so content receives the available width; the local inspector exposes those facts together with full payloads, provenance, schemas, and request timing. The Overview uses recorded start/duration and token-boundary facts without fabricating live elapsed time, and its inclusive focus behavior matches the interaction users already know from Chrome DevTools Network. Focused component tests pin tail following, timing projection, delayed detail disclosure, folding, record and interval selection, entity-specific tabs, and running/error semantics; the assembled Web snapshot pins the ledger, Overview timing details, and inspector through the real client composition.

.agents/notes/implemented/feature/2026-07-27-trajectory-inspection-ledger.zh.md

@@ -21,7 +21,8 @@ Status: implemented
 - 调用 schema 来自当前生效且已记录的请求头。无密钥快照 fixture（测试前置数据）有意将该目录替换为非数组 token `{{tools}}`，持久化检查边界会将其视为不可用，而不是尝试投影或虚构 schema。
 - 选择记录或请求后，轨迹视图内部会打开检查器，其标签页和概览区域随实体类型变化：Markdown 消息提供渲染、源码、来源和层级视图；工具提供 JSON 载荷／结果和 schema 视图；请求提供选项、用量、计时和结果跳转。图片以媒体形式渲染，而不是显示为序列化数据。
 - 折叠轮次时保留其第一条记录，将后续行替换为紧凑的步骤和工具调用数量；折叠助手时对其工具调用后代应用相同交互。全局控件可以分别折叠或展开这两个层级。
-- 移除独立的 waterfall（瀑布式事件）标签页。固定在记录表上方的 Overview 区域将所有 `startedAt` 已知的记录按各自耗时投影到三条语义计时轨道。向左或向右拖动会提交包含边界的区间筛选：任何活动区间与所选区间相交的记录都会保留，计时未知的记录会从聚焦后的记录表中移除，清除选择则恢复完整分支。聚焦后，Overview 区域仍保留完整时间范围，以便在不失去方位的情况下调整或清除选择。
+- 移除独立的 waterfall（瀑布式事件）标签页。固定在记录表上方的 Overview 区域将所有 `startedAt` 已知的记录按各自耗时投影到三条语义计时轨道。已完成的助手时间条以首个非空 token 增量为分界，用不同颜色按真实比例表示 TTFT 与解码时间；计时不完整时退化为单一助手色。悬停 500 ms 后会显示精确起止时刻、总耗时、TTFT 和解码时间，而不依赖浏览器原生 tooltip 的延迟。向左或向右拖动会提交包含边界的区间筛选：任何活动区间与所选区间相交的记录都会保留，计时未知的记录会从聚焦后的记录表中移除，清除选择则恢复完整分支。滚轮手势用于缩放时间域。右键单击会清除区间选择；右键拖动则只会平移已放大的 viewport，不会改变该选区。聚焦后，Overview 区域仍保留完整时间范围，以便在不失去方位的情况下调整或清除选择。
+- 实时历史更新仅在用户已经跟随记录表末尾时保留底部位置。向上滚动会清除跟随状态，因此流式分块和新追加的记录不会打断对旧记录的检查。
 - 此局部检查器与会话级 Chat 详情栏相互独立。在窄屏下，检查器会覆盖记录表，并且仍可通过键盘或指针关闭。
 
 ## 曾考虑的替代方案
@@ -40,4 +41,4 @@ Status: implemented
 
 ## 后果
 
-轨迹视图在保留轮次与请求定位的同时，每个视口可以显示更多有效记录。上下文 `rewrite` 与压缩保持在周边历史中的原始位置，`rewind` 则建立仅继承保留前缀的后继分支。主记录表省略 token 用量和耗时，让内容获得可用宽度；局部检查器展示这些数据以及完整载荷、来源、schema 和请求计时。Overview 区域使用记录的开始时间与耗时数据，而不虚构实时流逝时间，其包含边界的聚焦行为与用户熟悉的 Chrome DevTools Network 交互一致。针对性组件测试锁定投影、折叠、记录与区间选择、实体特定标签页和运行／错误语义；组装后的 Web 快照则通过真实客户端组合锁定记录表、Overview 区域与检查器。
+轨迹视图在保留轮次与请求定位的同时，每个视口可以显示更多有效记录。上下文 `rewrite` 与压缩保持在周边历史中的原始位置，`rewind` 则建立仅继承保留前缀的后继分支。主记录表省略 token 用量和耗时，让内容获得可用宽度；局部检查器展示这些数据以及完整载荷、来源、schema 和请求计时。Overview 区域使用记录的开始时间、耗时与 token 边界数据，而不虚构实时流逝时间，其包含边界的聚焦行为与用户熟悉的 Chrome DevTools Network 交互一致。针对性组件测试锁定末尾跟随、计时投影、延迟展示详情、折叠、记录与区间选择、实体特定标签页和运行／错误语义；组装后的 Web 快照则通过真实客户端组合锁定记录表、Overview 计时详情与检查器。