Chat + tool-call storytelling
Two forgetting modes for different needs:
A uses forget_node(soft) to hide a node
from retrieval (reversible) and
forget_by_policy(dry_run) to preview bulk pruning
candidates; B uses forget_node(cascade)
for deep cleanup and gdpr_erase for permanent,
audit-logged deletion. GDPR-compliant forgetting is a unique
differentiator — no competitor offers this.