agent-orchestrator/.changeset/opencode-tmpdir-and-shared-cache.md

@aoagents/ao-core	@aoagents/ao-cli	@aoagents/ao-plugin-agent-opencode
patch	patch	patch

opencode: bound /tmp blast radius and consolidate session-list cache

Addresses review feedback on PR #1478:

• TMPDIR isolation. Every opencode child we spawn now points at
  ~/.agent-orchestrator/.bun-tmp/ via TMPDIR/TMP/TEMP. Bun's
  embedded shared-library extraction lands there instead of the system
  /tmp, so the cli janitor only ever sweeps AO-owned files. Other
  users' or other applications' Bun artifacts on a shared host can no
  longer be touched by the regex.
• Single shared session-list cache. Core and the agent-opencode
  plugin previously kept independent caches; per poll cycle the system
  spawned at least two opencode session list processes instead of
  one. Both consumers now use the shared cache exported from
  @aoagents/ao-core (getCachedOpenCodeSessionList).
• TTL no longer covers the send-confirmation loop. The cache TTL
  dropped from 3s to 500ms so the
  updatedAt > baselineUpdatedAt delivery signal in
  sendWithConfirmation actually fires. Concurrent callers still
  share the in-flight promise.
• Delete invalidates the cache. deleteOpenCodeSession now calls
  invalidateOpenCodeSessionListCache() on success so reuse, remap,
  and restore code paths cannot observe a deleted session id within
  the TTL window.
• Janitor reliability. sweepOnce now filters synchronously
  before allocating per-file promises (matters on hosts with thousands
  of /tmp entries), and stopBunTmpJanitor() is now async and awaits
  any in-flight sweep so SIGTERM cannot exit while unlink is mid-flight.
• Janitor observability. The sweep callback in ao start now logs
  successful reclaims, not just errors, so operators can confirm the
  janitor is doing useful work.