feat(scheduler-sim-decision-trace): capture decision outcomes and reconstructed dispatches

Task 2.3: dispatch rows with limit charges listed separately and
resolved through the job's matched limits (raw-number fallback), pend
reason set deep-copied, 50 hosts in detail with the rest aggregated,
and RECONSTRUCTED records holding the dispatch outcome.

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

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

@@ -97,7 +97,7 @@
   - Done when capture tests pass under ASAN showing that limit rows are never reported as shortfalls, scope strings are correct, and each scope keeps the right rows.
   - _Requirements: 4.1, 4.2, 5.4, 5.5_
 
-- [ ] 2.3 Capture decision outcomes and reconstructed dispatches, test first
+- [x] 2.3 Capture decision outcomes and reconstructed dispatches, test first
   - **Dispatch:** per-host allocation rows and shared rows, with limit charges listed separately.
     - A limit charge is identified by the limit flag, or by its name prefix when the resource is unknown.
     - It is resolved to its limit by name through the job's matched limits. An unresolved charge falls back to a raw number.
@@ -349,3 +349,4 @@
 - 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.
+- 2.3: the outcome capture functions are `sched_trace_capture_dispatch`, `sched_trace_capture_pend` and `sched_trace_rec_reconstructed`, declared in trace.h; 3.x and 5.3 call them. Limit charges are classified by the limit flag or a `limit=` prefix and resolved via glimits (shared) or the worker's hlimits (host, worker looked up by host name). An unresolved charge has `limited_res == NULL`, which is the raw-number fallback. Shared pend entries carry host "" and are treated as host-less. For 4.1: limit totals over omitted hosts have a scope without the host, and a NULL host name yields the scope "h=". Follow-up (low): capture's `key_find`/`vget` on resmgr/workers run without the RTTI read lock that `sched_get_worker` takes. That is safe while the sim runs in lock-step; the 2.4 split may wrap them.