Open chat file links at the referenced line (#2309)

* fix(app): open chat file links at referenced lines

Pass chat file locations through the editable CodeMirror path so opening a reference selects and scrolls to its requested line. Cover the real assistant-link flow with a browser regression.

* fix(app): repeat chat file navigation

Track file navigation separately from stable tab identity so reopening the same path and line recenters both editable and read-only panes. Extend the browser regression to cover moving away and clicking the same link again.

* test(app): stabilize repeated file link navigation

packages/app/src/panels/file-panel.tsx

@@ -30,7 +30,7 @@ function useFilePanelDescriptor(target: { kind: "file"; path: string }) {
 
 function FilePanel() {
   const { t } = useTranslation();
-  const { serverId, workspaceId, target } = usePaneContext();
+  const { serverId, workspaceId, target, fileNavigationRevision } = usePaneContext();
   const workspaceDirectory = useWorkspaceDirectory(serverId, workspaceId);
   invariant(target.kind === "file", "FilePanel requires file target");
   if (!workspaceDirectory) {
@@ -40,7 +40,14 @@ function FilePanel() {
       </View>
     );
   }
-  return <FilePane serverId={serverId} workspaceRoot={workspaceDirectory} location={target} />;
+  return (
+    <FilePane
+      serverId={serverId}
+      workspaceRoot={workspaceDirectory}
+      location={target}
+      navigationRevision={fileNavigationRevision ?? 0}
+    />
+  );
 }
 
 export const filePanelRegistration: PanelRegistration<"file"> = {

packages/app/src/panels/pane-context.tsx

@@ -8,6 +8,7 @@ export interface PaneContextValue {
   workspaceId: string;
   tabId: string;
   target: WorkspaceTabTarget;
+  fileNavigationRevision?: number;
   openTab: (target: WorkspaceTabTarget) => void;
   closeCurrentTab: () => void;
   retargetCurrentTab: (target: WorkspaceTabTarget) => void;