Both files existed only on disk since the design phase (2026-08-03) and
were never committed despite ~40 implementation commits landing since.
Also corrects design.md drift found by /kiro-validate-impl: the File
Structure Plan and BuiltinFcfsPicker sections claimed plugins/fcfs.c
would be rewritten in place, but the actual implementation added a new
plugins/builtin_fcfs.c and deliberately kept fcfs.c untouched as the
job_elect_fn compat-wrapper's exercise target. Updates the directory
tree to the real file layout (core_events/session/clock.c, sim.c/
sim_loop.c/sim_record.c/sim_verify.c, snapshot/recording/repl splits,
test_e2e_capnp.c vs the planned test_replay_format.c, test_sched_admin_dispatch.c
vs test_sched_admin.c), and adds two Open Questions/Risks entries for
the AC 3 tlog-logging-integration gap and this fcfs.c/builtin_fcfs.c
documentation gap, both found during validation.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
