fix(app): paginate canonical timeline catch-up to avoid relay 1009 disconnect loop (#657)

@fireblue diagnosed the production failure mode: long canonical timeline catch-up could exceed the relay WebSocket frame cap, close with 1009, and send clients into a reconnect loop. Their seatbelt fix also removed the `limit: 0` footgun that let app callers request an unbounded frame.

This maintainer pass keeps that diagnosis and redirects the UX around bounded projected pages:

- initial agent load fetches the latest canonical tail
- app resume/reconnect re-fetches the latest tail instead of chaining after-cursor pages
- in-stream gaps still use bounded after-cursor catch-up
- older history loads explicitly when the user scrolls to the oldest edge
- shared page size is TIMELINE_FETCH_PAGE_SIZE = 100 projected timeline items, matching the daemon's canonical projection semantics rather than raw delta chunks

Original diagnosis and fix by @fireblue.

Co-authored-by: Mohamed Boudra <boudra.moha@gmail.com>

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

@@ -961,6 +961,7 @@ function ChatAgentContent({
                 canFinalizePendingCreate={canFinalizePendingCreate}
                 routeBottomAnchorRequest={routeBottomAnchorRequest}
                 hasAppliedAuthoritativeHistory={hasAppliedAuthoritativeHistory}
+                toast={panelToast.api}
                 onOpenWorkspaceFile={onOpenWorkspaceFile}
               />
             </ReanimatedAnimated.View>
@@ -1018,6 +1019,7 @@ function AgentStreamSection({
   canFinalizePendingCreate,
   routeBottomAnchorRequest,
   hasAppliedAuthoritativeHistory,
+  toast,
   onOpenWorkspaceFile,
 }: {
   streamViewRef: React.RefObject<AgentStreamViewHandle | null>;
@@ -1029,6 +1031,7 @@ function AgentStreamSection({
   canFinalizePendingCreate: boolean;
   routeBottomAnchorRequest: RouteBottomAnchorRequest;
   hasAppliedAuthoritativeHistory: boolean;
+  toast: ReturnType<typeof useToastHost>["api"];
   onOpenWorkspaceFile?: (input: { filePath: string }) => void;
 }) {
   const streamItemsRaw = useSessionStore((state) =>
@@ -1163,6 +1166,7 @@ function AgentStreamSection({
       pendingPermissions={pendingPermissions}
       routeBottomAnchorRequest={routeBottomAnchorRequest}
       isAuthoritativeHistoryReady={hasAppliedAuthoritativeHistory}
+      toast={toast}
       onOpenWorkspaceFile={onOpenWorkspaceFile}
     />
   );