promo-manager: skipPromo does not trigger the next queued promo

[vanilla-wave]

Problem

When the active promo is closed via finishPromo/cancelPromo, closePromo calls triggerNextPromo and the next queued promo starts. skipPromo clears the active promo and removes it from the queue, but never calls triggerNextPromo — so pending promos stay in the queue until some unrelated requestStart/sendEvent happens.

Real paths that hit this:

• the README pattern useUnmount(() => skipPromo());
• onboarding integration: closeHint -> skipPromo (initOnboardingIntegration).

A user closes a hint, and the next queued promo silently never shows.

Repro

const controller = new Controller(testOptions);

await controller.requestStart('boardPoll'); // active
await controller.requestStart('ganttPoll'); // pending
controller.skipPromo('boardPoll');

expect(controller.state.base.activePromo).toBe('ganttPoll'); // FAILS: null

Where

• src/promo-manager/core/controller.ts — skipPromo (missing triggerNextPromo after clearing active)