fix(chat): keep a long turn's Edited N files card whole across the page cut (#86)

The reported turn (/vp-auto, ~120 messages) showed "Edited 1 file": the
chat loads the newest 50 messages, and the turn's other Write
(rbac_routes_test.go, +176) was in the part before the page.

- turnCarry (agent-edits.js): every message the route's sliding window
  drops goes through it; it keeps the file changes since the last prompt it
  dropped (a dropped call whose result is on the page, and dropped
  subagents, included).
- A Claude page that starts mid-turn answers them as `turn_edits`; the
  chat keeps the one from the page that holds its oldest message and adds
  it to that turn's card.

Files a turn changed through Bash (python/sed writing a file) are still not
listed: nothing in the transcript says which files a command wrote.

client/src/components/conversation/ConversationView.tsx

@@ -78,7 +78,12 @@ import { useSpin } from "../../hooks/useSpin";
 import { useOnScreen, isShown } from "../../hooks/useOnScreen";
 import { throttle } from "../../lib/throttle";
 import { useTranslation } from "react-i18next";
-import type { TranscriptMessage, TranscriptInfo, WSMessage } from "../../lib/types";
+import type {
+  TranscriptMessage,
+  TranscriptInfo,
+  TranscriptResult,
+  WSMessage,
+} from "../../lib/types";
 
 // Catch-up poll interval. Claude Code only fires hooks on PreToolUse /
 // PostToolUse / Stop, which means a user-typed message (no hook) and any
@@ -175,6 +180,8 @@ function ConversationViewPane({
     initialTranscriptId ?? null
   );
   const [hasMore, setHasMore] = useState(false);
+  // The edits of the turn the oldest loaded page starts inside of (`turn_edits`).
+  const [leadEdits, setLeadEdits] = useState<TranscriptResult["turn_edits"]>(undefined);
   const [error, setError] = useState<string | null>(null);
   const [transcripts, setTranscripts] = useState<TranscriptInfo[]>([]);
   const [showNewMsg, setShowNewMsg] = useState(false);
@@ -283,6 +290,7 @@ function ConversationViewPane({
         if (cancelled) return;
         setNotStarted(false);
         setMessages(result.messages);
+        setLeadEdits(result.turn_edits);
         setTotal(result.total);
         setHasMore(result.has_more);
         lastLineRef.current = result.last_line;
@@ -343,6 +351,7 @@ function ConversationViewPane({
         // Seed the view in a single render so the user sees the whole
         // catch-up batch instead of a blank panel followed by a partial one.
         setMessages(result.messages);
+        setLeadEdits(result.turn_edits);
         firstLineRef.current = result.first_line;
         setHasMore(result.has_more);
       } else {
@@ -487,6 +496,7 @@ function ConversationViewPane({
       firstLineRef.current = result.first_line;
 
       setMessages((prev) => [...result.messages, ...prev]);
+      setLeadEdits(result.turn_edits);
       setHasMore(result.has_more);
 
       // Preserve scroll position (don't jump to top)
@@ -686,6 +696,7 @@ function ConversationViewPane({
               stopped={stopped}
               agentLinks={agentLinks}
               compact={compact}
+              leadEdits={leadEdits}
               sessionId={
                 selectedTranscript && selectedTranscript !== "main" ? undefined : sessionId
               }

client/src/components/conversation/MessageList.tsx

@@ -172,6 +172,9 @@ interface MessageListProps {
   /** A subagent's conversation inside its step: tight spacing, and the task
    *  the orchestrator gave it reads as the prompt it is. */
   compact?: boolean;
+  /** The files the first, cut-off turn changed before `messages` begins (the
+   *  transcript page's `turn_edits`): counted in that turn's card. */
+  leadEdits?: TranscriptContent["edits"];
 }
 
 /** Build a map from tool_use id → tool_result for matching */
@@ -493,6 +496,8 @@ type Item =
 const EDIT_TOOLS = new Set(["Write", "Edit", "MultiEdit", "NotebookEdit"]);
 // A subagent's result carries the files IT changed (`edits`): they count too.
 const AGENT_TOOLS = new Set(["Agent", "Task"]);
+// The stand-in for the part of a turn the page cut off: its `edits` count.
+const LEAD = "__lead_edits";
 
 /** A line that is only Claude Code's local-command plumbing — the caveat it
  *  writes first, the command, what the command printed — or null for
@@ -517,11 +522,18 @@ export function localCommand(
   return { name, output, error };
 }
 
-export function chatItems(messages: TranscriptMessage[], keys: string[]): Item[] {
+export function chatItems(
+  messages: TranscriptMessage[],
+  keys: string[],
+  leadEdits?: TranscriptContent["edits"]
+): Item[] {
   const items: Item[] = [];
   // The file-changing calls of the turn so far, closed into one card when the
-  // human speaks again (or the list ends).
-  let edits: TranscriptContent[] = [];
+  // human speaks again (or the list ends) — starting with what the page's
+  // cut-off first turn changed before it.
+  let edits: TranscriptContent[] = leadEdits?.length
+    ? [{ type: "tool_use", name: LEAD, edits: leadEdits }]
+    : [];
   // The turn's prompt time, its newest assistant line and its output so far,
   // for the "Done in …" line under a turn that ended.
   let start: string | null = null;
@@ -684,8 +696,8 @@ function EditedFilesCard({
   const byAgent = new Set<string>();
   for (const b of blocks) {
     const r0 = b.id ? toolResultMap.get(b.id) : undefined;
-    if (AGENT_TOOLS.has(b.name ?? "")) {
-      for (const e of r0?.edits ?? []) {
+    if (AGENT_TOOLS.has(b.name ?? "") || b.name === LEAD) {
+      for (const e of (b.name === LEAD ? b.edits : r0?.edits) ?? []) {
         if (!files.has(e.path)) byAgent.add(e.path);
         const f = files.get(e.path) ?? { added: 0, removed: 0, counted: false };
         f.added += e.added;
@@ -798,6 +810,7 @@ function MessageListView({
   sessionId,
   agentLinks,
   compact = false,
+  leadEdits,
 }: MessageListProps) {
   const { t } = useTranslation("sessions");
   const toolResultMap = useMemo(() => buildToolResultMap(messages), [messages]);
@@ -823,9 +836,10 @@ function MessageListView({
               m.sender === "orchestrator" ? { ...m, sender: "user" as const } : m
             )
           : messages,
-        keys
+        keys,
+        leadEdits
       ),
-    [messages, keys, compact]
+    [messages, keys, compact, leadEdits]
   );
   const agents = useMemo(
     () => (live ? backgroundAgents(messages, toolResultMap) : []),

client/src/components/conversation/__tests__/MessageList.edits.test.tsx

@@ -6,7 +6,8 @@
  * to the caller, and a row (or the header, every file) dragged as `@path`
  * attachments for a prompt box. Files a subagent changed (its Agent
  * result's `edits`, read from its own transcript) are counted in the same
- * card, never as an artifact.
+ * card, never as an artifact; so are the files a turn changed before the
+ * loaded page began (`leadEdits`, the page's `turn_edits`).
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 import { describe, it, expect, vi } from "vitest";
@@ -174,4 +175,26 @@ describe("the Edited N files card", () => {
     expect(within(card).getByText("report.html")).toBeTruthy();
     expect(screen.queryByTestId("artifact-card")).toBeNull();
   });
+
+  it("adds what the cut-off first turn changed before the page to that turn's card", () => {
+    render(
+      <MessageList
+        loading={false}
+        leadEdits={[{ path: "/w/rbac_test.go", added: 176, removed: 0, counted: true }]}
+        messages={[
+          call("1", "Write", "/w/handler_test.go"),
+          result("1", { added: 113, removed: 0 }),
+          user("what changed?"),
+          call("2", "Edit", "/w/x.go"),
+          result("2", { added: 1, removed: 0 }),
+        ]}
+      />
+    );
+    const [first, second] = screen.getAllByTestId("edited-files");
+    expect(first!.textContent).toContain("Edited 2 files");
+    expect(within(first!).getByText("rbac_test.go")).toBeTruthy();
+    expect(within(first!).getByText("handler_test.go")).toBeTruthy();
+    // The next turn's card is its own.
+    expect(second!.textContent).toContain("Edited 1 file");
+  });
 });

client/src/lib/types.ts

@@ -3324,6 +3324,10 @@ export interface TranscriptResult {
   last_line: number;
   /** JSONL line number of the first message in this page. */
   first_line: number;
+  /** Claude only, when the page starts in the middle of a turn: the files
+   *  that turn changed before the page's first message — the chat adds them
+   *  to the turn's "Edited N files" card. */
+  turn_edits?: { path: string; added: number; removed: number; counted: boolean }[];
 }
 
 /** One entry in a session's transcript picker (main agent, a subagent, or a