feat(npcs): free rotate overlays and drop session zoom tools

Drag the top-edge handle to rotate the whole frame with the avatar; remove unused zoom controls from the session NPC window.

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

app/renderer/control/ControlApp.tsx

@@ -1631,20 +1631,15 @@ export function ControlApp() {
                 <NpcsSceneOverlay
                   items={items}
                   editable
-                  zoomTool={npcsOverlay?.zoomTool ?? null}
                   showClose
                   closeLabel={t('npcs.closeOverlay')}
+                  rotateLabel={t('npcs.rotateOverlay')}
                   onClose={() => {
                     void npcsApi.dispatch({ kind: 'hide' });
                   }}
                   onLayoutChange={(npcId, layout) => {
                     void npcsApi.dispatch({ kind: 'layout.set', npcId, layout });
                   }}
-                  onZoomAt={(npcId, nx, ny) => {
-                    void npcsApi.dispatch(
-                      npcId ? { kind: 'zoomAt', nx, ny, npcId } : { kind: 'zoomAt', nx, ny },
-                    );
-                  }}
                 />
               );
             })()}