Convert on_job_start/on_job_finish/on_job_fail/on_job_postdone to
validate and durably append only -- BEFORE_EVENT validation hook
unchanged, AFTER_EVENT (post-mutation) hook no longer fires at
receipt, live state mutation removed. Adds persist_submit_job_fact()
(persist.c) since the durable append previously lived inside the
very AFTER_EVENT hook this task silences; wire format is unchanged
and identical to what apply_committed_entry() already routes.
mark_job_start/mark_job_finish (single caller each) renamed in place
to record_job_start_fact/record_job_finish_fact. mark_job_fail/
mark_job_update (shared with job_ctrl's client-command path, out of
boundary) left untouched; new durable-append-only siblings
record_job_fail_fact/record_job_update_fact added instead.
Accepts a narrow, permanent regression: on_job_postdone's finish_time
anomaly backstop has no wire-format equivalent and is dropped
(affects only a rare no-prior-exit-status path).
Two critical hazards discovered by review, documented in tasks.md,
MUST be resolved before task 6 wires apply_committed_entry() into a
live path: (1) persist_job_hook_fun still fires on HOOK_DETAIL_JOB_UPDATE
and will double-append every live-applied fact; (2) record_job_fail_fact/
record_job_update_fact precompute a final state that can be silently
clobbered by a concurrent intervening fact once apply is deferred by
the commit round-trip.
Rongsong Shen
23cbfb48e1