fix(web): keep older trajectory history loadable

.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: 74ed1f8ec6f6efcbf77e9caec7e254cb114efbd9
-2026-07-27-trajectory-inspection-ledger.zh.md: be648cb73478037979fd941753129b7c68be5085
+2026-07-27-trajectory-inspection-ledger.md: 7f97bc395ed694a0a750d3b744cc9887834ef32f
+2026-07-27-trajectory-inspection-ledger.zh.md: 34bb8741124c410fe06ec18bdde801caa987f4fb

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

@@ -21,7 +21,7 @@ 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 content, source fields, provider/model fields, and hierarchy views; tools add JSON payload/result and schema views; Requests add options, usage, timing, and result navigation. Scrollable Summary regions keep their scrollbar thumbs transparent until hover or `focus-within`, while retaining the scrollbar reservation and scroll behavior. 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.
-- A long ledger initially positions the loaded tail at the bottom and mounts only the viewport's row window plus bounded overscan. Request-only separators join the next measurable virtual item, with a terminal separator retaining its own fixed clearance, so the virtualizer never owns a zero-height item. Semantic DOM-safe row keys and ARIA indexes expose identity independently from mount position. A tail with known older history virtualizes immediately even when its loaded projection is below the ordinary row threshold. Stable-key virtualizer anchoring preserves the visible item across prepends and appends; the manual scroll-height fallback applies only when completing pagination disables virtualization. Selection, timeline focus, folding, search, and bottom following address records by stable event or tool-call identity rather than requiring their DOM rows to exist. An explicit loading row covers records until initial positioning finishes and while an older Session page is pending.
+- A long ledger initially positions the loaded tail at the bottom and mounts only the viewport's row window plus bounded overscan. Request-only separators join the next measurable virtual item, with a terminal separator retaining its own fixed clearance, so the virtualizer never owns a zero-height item. Semantic DOM-safe row keys and ARIA indexes expose identity independently from mount position. A tail with known older history virtualizes immediately even when its loaded projection is below the ordinary row threshold. Stable-key virtualizer anchoring preserves the visible item across prepends and appends; the manual scroll-height fallback applies only when completing pagination disables virtualization. Selection, timeline focus, folding, search, and bottom following address records by stable event or tool-call identity rather than requiring their DOM rows to exist. An explicit loading row covers records until initial positioning finishes. While an older Session prefix remains unloaded, an interactive first row precedes the loaded records and requests one older page; the same row becomes a disabled loading status for a pending page and disappears only when paging completes.
 - The separate Waterfall tab is removed. A fixed Overview above the ledger projects every loaded record with known `startedAt` onto three semantic timing lanes using its own duration. While an older prefix remains unloaded and the viewport includes the loaded domain's start, a neutral ellipsis control covers the truncated edge and loads one earlier page without assigning unknown history a fabricated duration; hovering that control suppresses the ordinary timeline cursor. 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 loaded ledger. 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. Tail following and virtualizer measurement react to row keys and heights rather than content identity, so text-only stream frames neither discard the measurement cache nor repeat a DOM scroll write.
 - Token streaming updates only the matching Trajectory Assistant Context, while publication is coalesced to at most once per animation frame. The target snapshot preserves the existing stage, layout, Request numbering, Overview, and search inputs; completed Assistant State retains assembled blocks, timing, and usage rather than every raw chunk payload, while Session keeps the raw Event window.

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

@@ -21,7 +21,7 @@ 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，Trajectory 内部会打开检查器，其标签页和概述区域随实体类型变化：Markdown 消息提供渲染内容、来源字段、提供方／模型字段和层级视图；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。可滚动的概述区域默认保持滚动条滑块透明，直到悬停或 `focus-within` 时才显示，同时保留滚动条预留空间和滚动行为。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，并用紧凑的步骤数和工具调用数替换后续所有行；折叠助手时对其工具调用后代应用相同操作。全局控件会折叠或展开这两个层级。
-- 长记录表初始时将已加载尾部置于底部，只挂载视口对应的行窗口及有界的额外缓冲行。仅含请求的分隔行并入下一个具备可测高度的虚拟项，末尾分隔行则保留固定留白，因此虚拟化器不会管理零高度项。可安全用于 DOM 的语义行键与 ARIA 索引使标识不依赖挂载位置。只要已知尾部之前仍有更早历史，即使当前已加载投影低于常规行数阈值，也会立即启用虚拟化。基于稳定键的虚拟化器锚定会在向前补页和尾部追加时保留当前可见项；只有分页完成导致虚拟化停用时，才使用手动滚动高度兜底。选择、时间线聚焦、折叠、搜索和末尾跟随均按稳定的事件或工具调用标识定位，不要求对应 DOM 行已存在。初始定位完成前以及更早 Session 页面仍在等待时，明确的加载行会遮住真实记录。
+- 长记录表初始时将已加载尾部置于底部，只挂载视口对应的行窗口及有界的额外缓冲行。仅含请求的分隔行并入下一个具备可测高度的虚拟项，末尾分隔行则保留固定留白，因此虚拟化器不会管理零高度项。可安全用于 DOM 的语义行键与 ARIA 索引使标识不依赖挂载位置。只要已知尾部之前仍有更早历史，即使当前已加载投影低于常规行数阈值，也会立即启用虚拟化。基于稳定键的虚拟化器锚定会在向前补页和尾部追加时保留当前可见项；只有分页完成导致虚拟化停用时，才使用手动滚动高度兜底。选择、时间线聚焦、折叠、搜索和末尾跟随均按稳定的事件或工具调用标识定位，不要求对应 DOM 行已存在。初始定位完成前，明确的加载行会遮住真实记录。更早的 Session 前缀仍未加载时，交互式首行位于已加载记录之前，可请求一页更早历史；页面加载期间，同一行会变为禁用的加载状态，仅在分页完成时消失。
 - 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` 已知的已加载记录按各自耗时投影到三条语义计时轨道。仍有更早前缀尚未加载且 viewport 包含已加载时间域起点时，中性的省略号控件会遮住截断边缘并加载一页更早历史，而不会为未知历史虚构耗时；悬停在该控件上会隐藏普通的时间线光标。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任一边界重叠的记录都会保留，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的已加载记录表。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。末尾跟随与虚拟化器测量仅响应行键和高度，而非内容标识，因此仅含文本的流式帧既不会丢弃测量缓存，也不会重复执行 DOM 滚动写入。
 - token 流式输出只更新命中的 Trajectory Assistant Context，发布则合并为每个 animation frame 最多一次。target snapshot 继续提供既有 stage、layout、请求编号、Overview 与搜索输入；已完成的 Assistant State 只保留组装后的 blocks、计时与 usage，不保留每条原始 chunk payload，而 Session 继续保存原始 Event 窗口。