feat(control): таймер сессии поверх сцены

Отдельное окно countdown с «Показать игрокам»; на превью — move/resize/rotate, на презентации тот же layout.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/renderer/control/ControlApp.tsx

@@ -61,6 +61,7 @@ import { useMaterialsOverlayState } from '../shared/materials/useMaterialsOverla
 import { NpcsSceneOverlay } from '../shared/npcs/NpcsSceneOverlay';
 import { useNpcsOverlayState } from '../shared/npcs/useNpcsOverlayState';
 import { SceneOverlayHost } from '../shared/sceneOverlay/SceneOverlayHost';
+import { SessionTimerLayer } from '../shared/sessionTimer/SessionTimerLayer';
 import { useSceneViewState } from '../shared/sceneView/useSceneViewState';
 import { SceneGridOverlay } from '../shared/grid/SceneGridOverlay';
 import { SceneTokensOverlay } from '../shared/tokens/SceneTokensOverlay';
@@ -1842,6 +1843,22 @@ export function ControlApp() {
               🎵
             </span>
           </Button>
+          <Button
+            variant="ghost"
+            iconOnly
+            title={t('control.timerTool')}
+            ariaLabel={t('control.timerTool')}
+            data-testid="control-timer-tool"
+            onClick={() => {
+              void api.invoke(ipcChannels.windows.openTimer, {}).catch((err) => {
+                console.error('[control] openTimer failed', err);
+              });
+            }}
+          >
+            <span className={styles.iconGlyph} aria-hidden>
+              ⏱
+            </span>
+          </Button>
           <Button
             variant="ghost"
             iconOnly
@@ -2980,6 +2997,7 @@ export function ControlApp() {
                 style={{ zIndex: 48 }}
               />
             ) : null}
+            <SessionTimerLayer viewport={previewContentRect} editable />
           </div>
         </Surface>