ludic.base, ludic.wildlife, ludic.npc: fact records reused, not made per fact

wl_fact made a new WildFact per fact, about one a frame, and Ludic never gives one back. ludic.base's q_unheld(q, pool, out) lists the records a queue no longer holds: neither waiting nor handed out by its last drain, which is good until the next drain. ludic.wildlife and ludic.npc now keep a pool, hand out a free record, and make a new one only when every record is held. Taking a record writes the state, so wl_fact / np_fact and the few callers holding their state read-only take it mut. Tests: q_unheld's rules (an empty drain holds on, the safe side); 3000 prints drained frame by frame use at most 4 records; 500 arrivals drained turn by turn use at most 4. base 37, wildlife 27, npc 17; all packages 420.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.wildlife/species.ludic

@@ -35,6 +35,9 @@ export property WildSpecies {
 
 export state WildlifeState {
   wl_facts: Queue<WildFact> = wl_facts__new()
+  wl_fpool: []WildFact = new []WildFact   # every fact record made, reused once no drain holds it
+  wl_ffree: []WildFact = new []WildFact   # of those, the ones free at the last look
+  wl_fnext: []int = words(1)              # the next of them to hand out
   wl_own: WildTable = null   # a guest's own animals, put away whole while it draws the host's
   wl_px: float = 0.0
   wl_pz: float = 0.0