Auto mode's MCP write checks gain a server-decided option and accept command rules

In auto mode, a classifier (an automatic checker) decides whether an action is safe instead of asking you. Allowed MCP tools that change things can be included in what it checks, based on where the mcpServerPolicy rule allowing them came from. That source can now also be a command, in addition to a command-line argument or the current session.

There is also a new path that hands the decision to the server. It applies only when the classifier's answer is to defer to the server and a matching mcpServerPolicy rule exists. It is off unless it is switched on remotely.

Whether these MCP write tools are included at all is still controlled by a remote switch that is off by default. The flag server has returned that switch on for this site's account and for an account with no sign-in, though it has not yet been read under this release.