feat(ui): replay run log in session terminal, drop per-row live tail

Set the task's log path when the run is created (not at completion) so the
session terminal can replay live output when the user navigates away and back
mid-run. Remove the now-redundant inline per-row live tail (LiveTail /
HasLiveTail / TaskMessageEvent) and scroll the terminal to end after the next
layout pass so wrapping lines aren't clipped.

src/ClaudeDo.Ui/Views/Islands/TaskRowView.axaml

@@ -175,20 +175,6 @@
             </Border>
 
           </StackPanel>
-
-          <!-- Live-tail row (visible when running + has tail) -->
-          <Border Classes="task-live-tail" IsVisible="{Binding HasLiveTail}">
-            <StackPanel Spacing="3">
-              <TextBlock Text="{Binding LiveTail}"
-                         TextTrimming="CharacterEllipsis" MaxLines="1"/>
-              <Grid Height="3" HorizontalAlignment="Stretch">
-                <Rectangle Fill="{DynamicResource Surface3Brush}"
-                           HorizontalAlignment="Stretch" RadiusX="1.5" RadiusY="1.5"/>
-                <Rectangle Fill="{DynamicResource MossBrush}"
-                           HorizontalAlignment="Left" Width="60" RadiusX="1.5" RadiusY="1.5"/>
-              </Grid>
-            </StackPanel>
-          </Border>
         </StackPanel>
 
         <!-- Star toggle -->