Adds ReplayCluster/ReplayHeader/SnapshotEntry/ReplayEvent/
SessionSummary/ReplaySession to controller.capnp, additively, first
task of Phase 3 (Foundation: Replay Wire Format).
Requirements.md's AC 20 capnp sketch isn't self-contained -- ReplayEvent's
union references JobStateChangeEvent/JobUpdateEvent (task 7.2's job),
SnapshotEntry.data/ReplayDecision's union reference SnapshotData/
DispatchDecision/PendDecision/PreemptDecision (task 7.3's job), none
of which exist yet. Resolved by verifying capnp's real constraints
against the toolchain directly: SnapshotData is an empty {} placeholder
(task 7.3 replaces its mapname'd C struct wholesale when adding the
real ~11 fields), ReplayDecision holds only {ts} (task 7.3 appends a
body union at new ordinals), and ReplayEvent's union holds only the 9
members with pre-existing backing types (Conf4Sched/SchedJobData/
WorkerData/ResourceData/ResValList/QueueConf/SchedJobRusages/Void),
deferring jobStateChange/jobUpdate to task 7.2 as new ordinals --
capnp requires strictly sequential ordinals with no holes, so this
split is compiler-mandated, not stylistic.
Round-trip test added to test_e2e_capnp.c. Full project build (all
binaries sharing this schema) and 1075/1075 controller_unit_test
verified clean.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019dw5WnN3DXStaEaPYfACU1
Rongsong Shen
68a6196517
