v3.9.0

v3.9.0 — 2026-08-18

• VS Code daemon ownership: Linux startup now delegates to aiosd.service and requires an authenticated TCP handshake before reporting readiness, preventing detached auto-spawn races with the systemd user service during desktop login.
• Audit-ledger concurrency integrity: standalone audit appends now acquire SQLite's writer slot with BEGIN IMMEDIATE before reading the predecessor hash, while callers already inside a larger control-plane or Product Factory transaction upgrade that transaction without opening a nested one. This prevents concurrent connections from selecting the same predecessor and forking the supposedly linear hash chain. A file-backed eight-writer regression test reproduces the old fork and verifies one linear chain; a separate test preserves transactional audit-call compatibility.
• HTTP/2 denial-of-service advisory: updated transitive h2 from 0.4.15 to 0.4.16, resolving RUSTSEC-2026-0258 (unbounded empty DATA frames). The lockfile change is intentionally limited to the patched crate and checksum; cargo audit reports zero known vulnerabilities.
• Tray graphical-session startup: the Linux user service is now enabled by graphical-session.target instead of default.target. After= alone did not pull the graphical target into the same boot transaction, so Qt could start several seconds before the Wayland socket existed, abort once, and recover only through Restart=on-failure. The unit remains ordered after and part of the graphical session, while a CI-backed service contract prevents regression to early boot ownership.
• Detached child lifecycle: the daemon's scheduler no longer drops spawned Child handles without waiting for them. A single process-wide reaper thread now polls all detached agent and extension children and consumes their exit status, preventing completed cron children from accumulating as zombies under aiosd; reaper startup/channel failure terminates and waits for the untracked child instead of leaking it.
• SQLite maintenance and recovery: added raios db check [--full], raios db checkpoint [--truncate], and raios db backup [--keep 1..=10]. Online snapshots are source- and destination-checked, SHA-256-recorded, owner-only on Unix, fsynced before success, and pruned to a bounded retention set without touching unrelated files. The recovery guide keeps restore offline and operator-controlled because workspace.db is shared by every agent and control-plane surface.
• 3.9.0 release: moved all six Rust crates to one inherited [workspace.package] version, prepared the CLI/daemon as 3.9.0 and the VS Code extension as 0.9.0, and finalized the signed release metadata.