0.5.6 shipped CdpTool inheriting BaseTool but missing the required
`register()` abstract method, so any host that registered the tool
crashed with `TypeError: Can't instantiate abstract class CdpTool`.
The browser package never reached MCP startup, taking the whole hanzo
MCP server with it.
This commit adds CdpTool.register() with the cdp-specific param surface
(action / method / params / tab_id / target_browser / client_id / timeout)
matching the BrowserTool registration pattern.
Yanking 0.5.6 from PyPI alongside this release; 0.5.7 is the canonical
0.5.x for the three-tool surface.
zeekay
48315d1937