CDP DOM-agent frameworks (browser-use and similar) could connect but saw a
blank page: navigation never refreshed their cached target url/title, and their
DOM build aborted with "Unknown domain: DOMSnapshot".
- Emit Target.targetInfoChanged after navigation (both CDP Page.navigate and
JS-initiated) carrying the post-nav url/title. Strict clients refresh a target
only on this event; it also fixes Puppeteer/Playwright page.url() tracking.
- Implement DOMSnapshot.captureSnapshot, built from the DOM with synthetic
geometry (no paint engine) and plausible computed styles, keyed by the same
backendNodeId as DOM.getDocument. Enough for tag/ARIA/accessibility element
detection; it runs only when a client requests it, so the fetch path is
unaffected. Coordinate clicking still requires a real layout engine.