fix: make resolving less jumpy

tui_test.go

@@ -1470,6 +1470,45 @@ func TestResolveToggleConfirmsAndUsesCurrentThreadState(t *testing.T) {
 	}
 }
 
+func TestResolvingSelectedThreadKeepsSelectionNearItsPreviousPosition(t *testing.T) {
+	tests := []struct {
+		name     string
+		selected int
+		wantID   string
+	}{
+		{name: "next thread", selected: 1, wantID: "c"},
+		{name: "previous thread at end", selected: 2, wantID: "b"},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			m := NewApp(nil, "o", "r", false, 50, time.Second)
+			m.screen, m.loading, m.focus = threadScreen, false, threadDetailPane
+			m.details.Threads = []ReviewThread{
+				{ID: "a", Path: "a.go"},
+				{ID: "b", Path: "b.go"},
+				{ID: "c", Path: "c.go"},
+			}
+			m.threadIndex = test.selected
+			resolvedID := m.details.Threads[test.selected].ID
+
+			updated, _ := m.Update(threadResolvedMsg{
+				threadID: resolvedID,
+				thread: ReviewThread{
+					ID: resolvedID, IsResolved: true, ViewerCanUnresolve: true,
+				},
+			})
+			m = updated.(App)
+
+			if got := m.details.Threads[m.threadIndex].ID; got != test.wantID {
+				t.Fatalf("selected thread = %q, want nearest thread %q", got, test.wantID)
+			}
+			if m.focus != threadDetailPane {
+				t.Fatalf("focus = %d, want detail pane", m.focus)
+			}
+		})
+	}
+}
+
 func TestPollingMarksNewThreadCommentsUnread(t *testing.T) {
 	m := NewApp(nil, "o", "r", false, 50, 10*time.Second)
 	m.screen, m.width, m.height = threadScreen, 80, 8