feat(scheduler-sim-decision-trace): capture shortfall and limit rows from the satisfaction check

Task 2.2: each checked row carries name, flags, value type, total,
in-use, reserved, requested and met (same comparison as unsatisfy_());
limit rows resolve through the scope's matched limits and never count as
shortfalls; the cluster-wide check keeps every row, a host only unmet
rows, which set its shortfall/limit verdict.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.kiro/specs/scheduler-sim-decision-trace/tasks.md

@@ -90,7 +90,7 @@
   - Done when capture tests over a fixture core and job pass under ASAN, showing exact copied values that do not change when the source structures change later.
   - _Requirements: 2.2, 2.3, 3.5_
 
-- [ ] 2.2 Capture shortfall and limit rows from the satisfaction check, test first
+- [x] 2.2 Capture shortfall and limit rows from the satisfaction check, test first
   - Each checked row carries the resource name, flags, value type, total, in-use, provisionally reserved, requested and met.
   - A row whose resource is flagged as a limit is a limit row. It is resolved to its limit through the scope's matched limits and carries the limit name, the scope instance (plus the host for host scope) and the limited resource's name.
   - The cluster-wide scope keeps every row. A host scope keeps only unmet rows, and these set the host's shortfall and/or limit verdict.
@@ -347,3 +347,5 @@
 - 1.7 OPEN for 5.3: the sim decision-free sites at sim_loop.c ~1327 (reconstructed dispatch) and ~1709 (drain loop) don't yet call `sched_trace_rec_free(d->trace)`, and the TRACE op still falls to the sim's switch defaults. 5.3 must add the early TRACE branch before verify/record/breakpoint, or sim_verify reports false mismatches and breakpoints count it as "NONE". decision.h forward-declares `struct xce_sched_trace_rec_s` rather than including sched/trace.h.
 - 1.8: `core->trace_ctl` and `core->trace_rec` are plain forward-declared pointers (core.h does not include sched/trace.h), and `xce_sched_core_fini()` clears them without freeing because core.c can't link the trace sources. test_trace_hooks_gate.c counts `sched_trace_rec_new` with a link-time wrap. Its "full allocation creates no record" check only becomes meaningful once 3.1 adds the per-job hook. The 11.3 check (non-interactive sim never publishes trace_ctl) is in 5.3.
 - 2.1: capture reads struct fields only and calls no scheduler functions, so the white-box tests need no extra sources. Policy name = ctl policy_name, else core->job_pick_plugin; the queue picker override is ignored because election always uses the core picker. Cluster-wide limit scope is stored as "u=..,q=..,p=.." ("" when unscoped); 2.2 should reuse split_vres_name/copy_scope and append "h=<host>". 4.1 must render selection_set/glimits_set false as "unavailable" and an ATTEMPT_REASONS entry with ncodes==0.
+- 2.2: rows go through `sched_trace_row()`, a model addition not named in the design, as CHECK_ROW (cluster-wide check, all rows) or HOST_ROW (host scope, unmet rows only). Host rows are held until the host verdict is stored and then stored one level deeper, each counting against the budget; they are dropped at summary level, where the verdict bits and limit tally are still set. Rows arriving outside an open check (`rec->check_open`) or a host scope are dropped, so 3.3/3.4 must open a host scope before host_iter's pre-filter calls `sched_check_host_satisfy` and must call `sched_trace_check_end` on every exit path of the cluster-wide check. 4.1 must render a NULL row name by its index, `limited_res == NULL` as a raw amount, and HOST_ROW at host depth + 1. Capture now calls librtti `vget()`, which every test already links.
+- 2.2 OPEN for 6.2: if `limit_row()` runs out of memory, `sched_trace_check_rows` returns early, so that row's LIMIT bit and later rows' SHORTFALL bits are lost. The verdict derived from rows then becomes SELECT and the Req 9.3 counts are off. This needs fault injection to test, so fix it in 6.2: keep setting the verdict bits and continue.