* perf(codex): share one launch-prep hook install across a spawn burst
Codex launch prep runs a full managed-hook install on every local PTY
spawn, and both install lanes serialize globally per Codex home. Opening
a multi-pane worktree therefore paid N full installs back to back, and a
resumed Codex pane prepares twice. Concurrent spawns for the same runtime
home now share one run; the promise is dropped as soon as it settles, so
the next launch still re-reads hooks.json and the user's trust state.
Also split the `host_env` spawn-timing phase, which spanned the entire
Codex preamble and pinned that cost on the env builder that ran last.
* refactor(codex): unify the two hook-install single-flight lanes
Both the WSL and launch-prep lanes now share one generic in-flight helper
instead of duplicating the map bookkeeping. Also routes the WSL launch-prep
install through the serialized variant, which closes the same per-spawn
serialization gap on WSL that the native lane just got.
* refactor: extract the shared in-flight run dedupe
The codex hook service and the GitHub conflict-summary cache had grown
near-identical private copies of the same single-flight helper. Both now
use one module, which also keeps the hook service clear of the 300-line
budget. The shared copy keeps the identity check on clear so a late settle
cannot evict a newer entry for the same key.
Neil
20a12a6a46