Voiceover review page overflows narrow viewports

### Description

The voiceover editing review page cannot fit a mobile viewport and has no responsive breakpoint for its three-column layout.

In `skills/byted-mediakit-voiceover-editing/templates/review-page/index.html`:

- `.left-panel` is fixed at 360px.
- `.right-panel` is fixed at 360px.
- `.center-panel` has `min-width: 640px`.
- No `@media` rule adapts or stacks these panels.

### Reproduction

At commit `0890278a6571e4190c1ab8cacd9becc147f74d9c`, serve the tracked template locally and inspect it at a 390px-wide viewport. Browser DOM measurement produced:

```text
document.documentElement.clientWidth = 390
document.documentElement.scrollWidth = 1098
```

The timeline/review controls extend well beyond the viewport and the right-side editing controls are off-screen. At a 1280px desktop viewport the three-column layout renders as intended, so this is specifically the missing responsive state rather than a general parse/render failure.

### Expected behavior

At narrow viewport widths, the page should stack, collapse, or otherwise resize its panels so the review controls remain reachable without a page-wide horizontal canvas.

### Impact

Users opening the generated review page on a phone or narrow embedded browser cannot reliably inspect and edit the voiceover result because primary controls are clipped/off-screen.

### Duplicate check

Open/closed issues, all PR states, the template's commit history, and responsive/mobile/overflow terms were searched. No equivalent report or active fix was found.

### Why there is no PR in this audit

This template has no frontend test/build harness or documented mobile interaction design. Choosing which panel should collapse, how the video/timeline should resize, and how the editing controls should be exposed on mobile requires a UX decision and browser validation against real rendered review data, which is not available on the Windows audit host without the MediaKit workflow and credentials.

Open skills/byted-mediakit-voiceover-editing/templates/review-page/index.html and inspect the three-panel layout at a 390px viewport using the documented DOM measurements. Decide how the panels should stack, collapse, or resize, then validate against real rendered review data in a browser. Done means the review controls remain reachable without page-wide horizontal overflow while the 1280px layout still works.

Written by the indexing model from the issue text.