mavweb: add notifications history page at /notifications

RecentNudges IPC method, store adapter, dispatch, and client proxy.
Web UI at /notifications showing recent nudge history with color-coded
outcomes, nav links from /dash and /history.

cmd/mavweb/handlers_test.go

@@ -52,6 +52,9 @@ type fakeCore struct {
 	revertNewID  int64
 	revertErr    error
 
+	// for handleNotifications tests
+	nudgesErr    error
+
 	// for handleHistory tests
 	historyFacts []ipc.Fact
 	historyErr   error
@@ -115,6 +118,9 @@ func (f *fakeCore) RecentFacts(_ context.Context, _ int) ([]ipc.Fact, error) {
 }
 
 func (f *fakeCore) RecentNudges(_ context.Context, _ int) ([]ipc.Nudge, error) {
+	if f.nudgesErr != nil {
+		return nil, f.nudgesErr
+	}
 	if f.dashErr != nil {
 		return nil, f.dashErr
 	}
@@ -549,6 +555,58 @@ func TestHandleDash(t *testing.T) {
 	})
 }
 
+// --- handleNotifications ---
+
+func TestHandleNotifications_NilCore_503(t *testing.T) {
+	t.Parallel()
+	rr := httptest.NewRecorder()
+	handleNotifications(rr, httptest.NewRequest(http.MethodGet, "/notifications", nil), nil)
+	if rr.Code != http.StatusServiceUnavailable {
+		t.Errorf("status = %d, want 503", rr.Code)
+	}
+}
+
+func TestHandleNotifications_CoreError_502(t *testing.T) {
+	t.Parallel()
+	core := &fakeCore{nudgesErr: ipc.ErrNudgeNotFound}
+	rr := httptest.NewRecorder()
+	handleNotifications(rr, httptest.NewRequest(http.MethodGet, "/notifications", nil), core)
+	if rr.Code != http.StatusBadGateway {
+		t.Errorf("status = %d, want 502", rr.Code)
+	}
+}
+
+func TestHandleNotifications_Renders(t *testing.T) {
+	t.Parallel()
+	core := &fakeCore{
+		nudges: []ipc.Nudge{
+			{Rule: "test-rule", Channel: "telegram", Message: "hello world", Outcome: "pending"},
+			{Rule: "other-rule", Channel: "voice", Message: "something happened", Outcome: "acted"},
+		},
+	}
+	rr := httptest.NewRecorder()
+	handleNotifications(rr, httptest.NewRequest(http.MethodGet, "/notifications", nil), core)
+	if rr.Code != http.StatusOK {
+		t.Fatalf("status = %d, want 200; body=%s", rr.Code, rr.Body.String())
+	}
+	body := rr.Body.String()
+	if !strings.Contains(body, "test-rule") {
+		t.Error("rendered output missing rule name")
+	}
+	if !strings.Contains(body, "telegram") {
+		t.Error("rendered output missing channel")
+	}
+	if !strings.Contains(body, "pending") {
+		t.Error("rendered output missing outcome")
+	}
+	if !strings.Contains(body, "hello world") {
+		t.Error("rendered output missing message")
+	}
+	if !strings.Contains(body, "other-rule") {
+		t.Error("rendered output missing second rule")
+	}
+}
+
 // --- handleHistory ---
 
 func TestHandleHistory(t *testing.T) {