feat(frontend): Remittances + ActivityLog wire live tail

src/pages/ActivityLog.tsx

@@ -1,4 +1,7 @@
 import { useActivity } from "@/hooks/useActivity";
+import { useTailStream } from "@/hooks/useTailStream";
+import { useMergedTail } from "@/hooks/useMergedTail";
+import { TailStatusPill } from "@/components/TailStatusPill";
 import { ActivityFeed } from "@/components/ActivityFeed";
 import { Skeleton } from "@/components/ui/skeleton";
 import { EmptyState } from "@/components/ui/empty-state";
@@ -6,7 +9,16 @@ import { ErrorState } from "@/components/ui/error-state";
 
 export function ActivityLog() {
   const { data, isLoading, isError, error, refetch } = useActivity({ limit: 200 });
-  const items = data?.items ?? [];
+
+  // SP5 live-tail wiring (sub-project 5, Phase 5 Task 23). The page has
+  // no existing kind filter UI (the plan calls out "filters by activity
+  // kind" but the current ActivityLog renders all events unfiltered),
+  // so we pass no `filterFn` to `useMergedTail` — every live-arriving
+  // activity event is shown. If a kind filter is added later, this is
+  // the place to thread it through.
+  const { status: tailStatus, lastEventAt: tailLastEventAt, forceReconnect } =
+    useTailStream("activity");
+  const items = useMergedTail("activity", data?.items ?? []);
 
   return (
     <div className="space-y-8 animate-fade-in">
@@ -31,6 +43,16 @@ export function ActivityLog() {
       ) : null}
 
       <div className="surface rounded-xl p-6">
+        <div className="flex flex-wrap items-center gap-3 mb-4">
+          {/* SP5: live-tail status pill, right-aligned in the toolbar. */}
+          <div className="ml-auto">
+            <TailStatusPill
+              status={tailStatus}
+              lastEventAt={tailLastEventAt}
+              onReconnect={forceReconnect}
+            />
+          </div>
+        </div>
         {isLoading ? (
           <div className="space-y-2">
             {Array.from({ length: 5 }).map((_, i) => (

src/pages/Remittances.test.tsx

@@ -10,6 +10,7 @@ import { describe, expect, it, vi, beforeEach } from "vitest";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import { Remittances } from "./Remittances";
 import { api } from "@/lib/api";
+import { useTailStore } from "@/store/tail-store";
 
 // Module-level mock: vitest hoists `vi.mock` calls above imports. We only
 // stub the method this page touches via the `useRemittances` hook.
@@ -23,6 +24,18 @@ vi.mock("@/lib/api", () => ({
   },
 }));
 
+// Mock the live-tail hook so the page renders the pill in the settled
+// `live` state without driving the real streamTail parser. The hook's
+// own test file (`useTailStream.test.ts`) covers the lifecycle in depth.
+vi.mock("@/hooks/useTailStream", () => ({
+  useTailStream: vi.fn(() => ({
+    status: "live",
+    lastEventAt: null,
+    error: null,
+    forceReconnect: vi.fn(),
+  })),
+}));
+
 /**
  * Minimal `render` helper using react-dom/client + act(). Mirrors the
  * `renderIntoContainer` helper in `Reconciliation.test.tsx` — see that
@@ -78,6 +91,10 @@ async function waitForText(
 describe("Remittances", () => {
   beforeEach(() => {
     vi.clearAllMocks();
+    // Singleton tail-store: clear the remittances slice between tests
+    // so a tail-arrival case (if added later) doesn't see rows from a
+    // previous test.
+    useTailStore.getState().reset("remittances");
   });
 
   it("renders a CAS adjustment label inside the expanded detail row", async () => {
@@ -146,4 +163,36 @@ describe("Remittances", () => {
     expect(document.body.textContent).toContain("PR-1");
     unmount();
   });
+
+  // -------------------------------------------------------------------
+  // Live-tail status pill (sub-project 5, Phase 5 Task 23, optional
+  // page-level test). Cheap smoke check: the toolbar renders the pill
+  // with the `live` label whenever the mocked stream is settled. The
+  // hook's lifecycle is covered exhaustively in its own test file.
+  // -------------------------------------------------------------------
+
+  it("test_status_pill_shows_live_in_toolbar", async () => {
+    (
+      api.listRemittances as unknown as ReturnType<typeof vi.fn>
+    ).mockResolvedValue({
+      items: [],
+      total: 0,
+      returned: 0,
+      has_more: false,
+    });
+
+    const { unmount } = renderIntoContainer(React.createElement(Remittances));
+
+    // Wait for the empty-state to mount — once the page body is rendered,
+    // the toolbar (and thus the pill) is in the DOM.
+    await waitForText("Remittances · awaiting first 835");
+
+    const pill = document.body.querySelector(
+      '[data-testid="tail-status-pill"]',
+    );
+    expect(pill).not.toBeNull();
+    expect(pill?.textContent).toContain("Live");
+
+    unmount();
+  });
 });

src/pages/Remittances.tsx

@@ -1,4 +1,4 @@
-import { Fragment, useState } from "react";
+import { Fragment, useMemo, useState } from "react";
 import { ChevronDown, ChevronRight, Receipt } from "lucide-react";
 import {
   Table,
@@ -15,9 +15,12 @@ import { ErrorState } from "@/components/ui/error-state";
 import { FilterChips, type FilterChipOption } from "@/components/ui/filter-chips";
 import { Pagination } from "@/components/ui/pagination";
 import { useRemittances } from "@/hooks/useRemittances";
+import { useTailStream } from "@/hooks/useTailStream";
+import { useMergedTail } from "@/hooks/useMergedTail";
+import { TailStatusPill } from "@/components/TailStatusPill";
 import { fmt } from "@/lib/format";
 import { cn } from "@/lib/utils";
-import type { CasAdjustment, RemittanceStatus } from "@/types";
+import type { CasAdjustment, Remittance, RemittanceStatus } from "@/types";
 
 const PAGE_SIZE = 25;
 
@@ -64,7 +67,25 @@ export function Remittances() {
     limit: PAGE_SIZE,
     offset: (page - 1) * PAGE_SIZE,
   });
-  const items = data?.items ?? [];
+
+  // SP5 live-tail wiring (sub-project 5, Phase 5 Task 23). The tail
+  // stream emits every remittance that lands — including ones that
+  // don't match the user's current `status` filter chip. Drop those
+  // tail items so a newly-arrived remit that wouldn't match the page's
+  // intent doesn't flash into the table. Base items are NOT filtered
+  // here (they reflect whatever the list query returned, matching the
+  // existing page behavior).
+  const tailFilterFn = useMemo(
+    () => (r: Remittance) => {
+      if (status && r.status !== status) return false;
+      return true;
+    },
+    [status],
+  );
+
+  const { status: tailStatus, lastEventAt: tailLastEventAt, forceReconnect } =
+    useTailStream("remittances");
+  const items = useMergedTail("remittances", data?.items ?? [], tailFilterFn);
 
   const total = items.reduce(
     (acc, r) => ({
@@ -126,15 +147,25 @@ export function Remittances() {
       </div>
 
       <div className="surface rounded-xl p-4">
-        <FilterChips
-          options={STATUS_OPTIONS}
-          value={status}
-          onChange={(v) => {
-            setStatus((v as RemittanceStatus | null) ?? null);
-            setPage(1);
-          }}
-          eyebrow="Status"
-        />
+        <div className="flex flex-wrap items-center gap-3">
+          <FilterChips
+            options={STATUS_OPTIONS}
+            value={status}
+            onChange={(v) => {
+              setStatus((v as RemittanceStatus | null) ?? null);
+              setPage(1);
+            }}
+            eyebrow="Status"
+          />
+          {/* SP5: live-tail status pill, right-aligned in the toolbar. */}
+          <div className="ml-auto">
+            <TailStatusPill
+              status={tailStatus}
+              lastEventAt={tailLastEventAt}
+              onReconnect={forceReconnect}
+            />
+          </div>
+        </div>
       </div>
 
       <div className="surface rounded-xl overflow-hidden">