fix(scheduler): sim mode force-dispatched recorded decisions past live capacity (bug-1836, bug-1838)

User-reported: replaying a captured session dispatched 44 single-slot jobs
onto a 22-slot host. Root cause traced through two layers:

- bug-1836: sim_reconcile_unaccounted_jobs() (the "Recorded-Decision
  Reconciliation" backstop) force-applied any recorded DISPATCH decision
  it found, with zero live capacity check. Added
  sim_reconciled_alloc_fits_capacity(), reusing the same
  sched_check_host_satisfy()/sched_check_shared_satisfy() admission checks
  the live picker/allocator path already uses.

- bug-1838: even with that gate, reconciliation still preempted every
  freshly-PEND job before the live picker/allocator got a turn each round
  -- unnecessary now that scheduler-sim-live-allocation gave sim mode the
  same real, capacity-checked picker/allocator threads normal mode uses.
  Narrowed reconciliation's trigger back to JOB_IS_RUN-only (undoing a
  2026-09-11 widening whose own justification no longer holds), so a
  freshly-pushed job now always flows through the same live, verified
  decision path as normal mode. Reconciliation now only ever fires for a
  job already RUN from before the replay's own observation window --
  the one case structurally invisible to the live picker.

Also logged (bug-1837, not fixed here, needs its own design decision):
sim_reconcile_unaccounted_jobs() calls a picker's on_dispatch() hook from
the driver thread instead of the allocator thread plugin.h documents it
belonging to -- currently inert since the only real picker plugin happens
to lock internally, but not contract-safe for a future lock-free one.

Fixing bug-1838 required re-examining every test exercising the old
PEND-inclusive trigger; several needed their fixtures corrected to
register a real worker (harmless before any capacity check existed), and
others needed their actual intent re-derived and their assertions
inverted or restated now that a PEND job is never eligible for
reconciliation. Dated correction notes added in place to the
scheduler-sim-eager-reconciliation spec, matching its own existing
2026-09-11 correction-note precedent.

Verified: full scheduler suite 85/85, independently re-confirmed by
running the four most affected binaries directly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/scheduler/testsuite/test_sim_resource_contention.c

@@ -236,6 +236,7 @@ int sched_account_jobs(xce_sched_core_t* core)
     return 0;
 }
 
+
 /* xce_sched_driver_on_decision()'s (driver.c) publish-side linker
  * dependencies -- never actually invoked: this test never registers a
  * decision callback, so every decision is simply recorded and dropped.