The channels the browser reported (already validated and capped).
OptionalChannelsThe cascade's folded channels section — agent layers plus the app layer.
OptionalClientThe client tools as the browser declared them at mint, if any.
OptionalClientThe app/static client-tool tiers to hand back to the browser, when resolved.
OptionalModelWhether the session model's configuration declares Privacy.ZeroDataRetention: true. Feeds the
agent's requireZeroDataRetentionFor exposure downgrade; leave unset (treated as false) when
the model could not be resolved, so the downgrade fails closed.
The registry, as the server reads it.
Input to BuildSessionChannelPolicy.