#11342: fix(browser): respect fullPage=false for viewport-only screenshots

## Summary The `captureBeyondViewport` CDP parameter was hardcoded to `true`, causing all screenshots to capture the full scrollable page regardless of the `fullPage` option. ## The Bug When calling `browser screenshot` with `fullPage=false` (the default), screenshots still captured the entire scrollable page instead of just the viewport. **Expected:** A 1280×800 viewport screenshot **Actual:** A 316×2000 full-page screenshot (scaled down) ## The Fix Make `captureBeyondViewport` conditional on the `fullPage` parameter: ```diff - captureBeyondViewport: true, + captureBeyondViewport: Boolean(opts.fullPage), ``` ## Testing Tested locally with: ```bash openclaw browser screenshot # viewport only openclaw browser screenshot --full-page # full page ``` Before fix: Both captured full page After fix: First captures viewport only, second captures full page <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR fixes screenshot capture behavior in `src/browser/cdp.ts` by making the Chrome DevTools Protocol `Page.captureScreenshot` option `captureBeyondViewport` depend on the caller’s `fullPage` flag. Previously it was hardcoded to `true`, so even the default `fullPage=false` path could capture content beyond the visible viewport. The change aligns viewport-only screenshots with expectations while preserving the existing full-page codepath (which already computes a content-sized `clip` via `Page.getLayoutMetrics`). <h3>Confidence Score: 5/5</h3> - This PR is safe to merge with minimal risk. - The change is narrowly scoped (one CDP parameter), matches the documented intent of `fullPage`, and does not alter surrounding logic besides gating `captureBeyondViewport` on `opts.fullPage`. No other call sites or types are affected, and the previous behavior was clearly incorrect per PR description. - No files require special attention <!-- greptile_other_comments_section --> _{(2/5) Greptile learns from your feedback when you react with thumbs up/down!} <!-- /greptile_comment -->