Plugins can now replace a built-in tool by passing override=True to
ctx.register_tool(). Without it, the registry rejects any registration
that would shadow an existing tool from a different toolset (unchanged
default behavior).
Unlocks the use case from #11049: drop-in replacement of browser/web
backends without forking core. Composes with the existing pre_tool_call
hook for runtime interception of any implementation.
The override is audit-logged at INFO so it surfaces in agent.log.
Teknium
016c772e7f