v0.6.0

0.6.0

• Periodic retain nudge. Every host now asks the agent, at most once every
  15 minutes per session, to retain whatever durable claim it has not stored
  yet -- a decision with its rationale, a constraint, a convention, a verified
  gotcha, a fact not cheaply rediscoverable, or a dated landmark -- and to
  store nothing otherwise. /clear has no hook that gives the agent a turn,
  and PreCompact never fires on it, so a long session used to lose what it
  had learned the moment the context went. The nudge is the same text on
  every host (ach-memory hook retain-nudge) and the throttle lives in one
  place (hooks/scripts/retain-nudge.sh). ACH_MEMORY_NUDGE_INTERVAL
  (seconds, default 900) tunes it.
• Wired as the host's "turn finished" event, never on prompt submission.
  Claude Code and Codex: Stop, whose stdout never reaches the model, so the
  nudge travels as {"decision": "block", "reason"} and costs one extra turn
  (hooks/scripts/stop.sh; stop_hook_active ends it). opencode:
  session.idle plus client.session.promptAsync. pi: agent_settled plus
  pi.sendMessage(..., {triggerTurn: true}). Both emulations carry their own
  loop guard, so a short interval nudges once per turn at worst, never forever.
• Codex trusts hooks per definition: after updating, open Codex once and press
  t in the hooks review. Until then Stop -- and any other untrusted plugin
  hook -- stays inactive.
• docs/hosts.md: the matrix row, and pi's compaction event is "not wired",
  not "does not exist" -- pi exposes session_before_compact.

No service change; the release is the plugin.