J2: sim picker casts+consumes; T5 raid-content warning

The post-J1 sweep had the casters clustered at 19–22% L12 clear, vs
martials at 70–80%. A per-round trace across 240 boss-room fights showed
why: autoResolveCombat dispatched !attack only — zero spell_casts, zero
mid-fight consumable uses across every caster class. The entire "caster
cliff" was the sim measuring a strawman where casters couldn't cast.

J2a teaches the sim's autoResolveCombat to mirror a competent prod
player: heal at low HP if an inventory consumable is available, otherwise
cast the highest-EV damage spell (slot or cantrip), otherwise swing.
BuildCharacter now seeds the known-spell list via ensureSpellsForCharacter
so the synthetic spellbook is populated. A -trace flag on the cmd
attaches the raw CombatEvent stream to the last combat of each run for
post-hoc diagnostics.

A first re-baseline (n=100, all 10 classes) showed Ranger regressed
-35.8pp — the picker was burning L3 slots on lightning_arrow when
Ranger's weapon chassis (Hunter's Mark + Extra Attack) was the better
play. Added simMartialFirstClass to gate the picker off for Ranger and
Paladin (whose default kit is also weapon-first / no damage spells).
J2c experimented with widening the picker to control + heal spells;
heal-spell preempt cost druid 10pp (slot heals are 10HP vs 40HP
consumables) and control-spell scoring at 22 cost warlock 6.6pp. Both
reverted. Corpora retained under baseline_j2c*.jsonl for the post-mortem
in sim_results/j2b_findings.md.

Post-J2 L12 leaderboard (baseline_j2a_v2_all10.jsonl, n=100):
  fighter 80.0, ranger 80.0, paladin 78.4, rogue 76.8,
  druid 61.6, mage 53.4, sorcerer 50.6, warlock 48.2,
  bard 40.4, cleric 39.0.

The caster cluster is dissolved; martials are within ±5pp of J1 (sweep
noise). Bard/cleric still trail, but it's no longer a sim artifact —
their defaultKnownSpells damage rosters cap at L2 and the picker can't
pick spells they don't have. That's a prod-level fix, deferred.

J3 trace (sim_results/j3_findings.md): T5 dragons_lair walls every solo
class at 0% (Infernax 546 HP vs solo player HP 110–175; ~25% boss HP
eaten before TPK across all classes). Per the J3 plan menu, this is
party-shaped content the engine doesn't yet have parties for. Surface
a TwinBee-voiced heads-up in handleDnDExpeditionCmd's start path and a
matching tag in !expedition list — players see "raid-shaped — solo
runs not yet survivable" before they spend outfitting coin. No combat
or class balance changes.

Files: cmd/expedition-sim/main.go +trace flag; expedition_sim.go picker
+ SimCombatSummary.Events + spellbook seed; dnd_expedition_cmd.go
raidContentWarning + list tag. All baselines + traces + findings
checked in under sim_results/.

internal/plugin/dnd_expedition_cmd.go

@@ -116,8 +116,12 @@ func (p *AdventurePlugin) expeditionCmdList(ctx MessageContext, c *DnDCharacter)
 	var b strings.Builder
 	b.WriteString(fmt.Sprintf("**Expeditions available at L%d** (you can enter zones up to 2 tiers above your current tier):\n\n", c.Level))
 	for i, z := range zones {
-		b.WriteString(fmt.Sprintf("**%d.** %s — _T%d, L%d–%d_  `!expedition start %s`\n",
-			i+1, z.Display, int(z.Tier), z.LevelMin, z.LevelMax, z.ID))
+		suffix := ""
+		if raidContentWarning(z.ID) != "" {
+			suffix = "  _⚠ raid-shaped — solo runs not yet survivable_"
+		}
+		b.WriteString(fmt.Sprintf("**%d.** %s — _T%d, L%d–%d_  `!expedition start %s`%s\n",
+			i+1, z.Display, int(z.Tier), z.LevelMin, z.LevelMax, z.ID, suffix))
 		b.WriteString(fmt.Sprintf("    %s\n", z.Atmosphere))
 	}
 	if exp, _ := getActiveExpedition(ctx.Sender); exp != nil {
@@ -269,10 +273,31 @@ func (p *AdventurePlugin) expeditionCmdStart(ctx MessageContext, c *DnDCharacter
 		b.WriteString(startLine)
 		b.WriteString("\n\n")
 	}
+	if w := raidContentWarning(zoneID); w != "" {
+		b.WriteString(w)
+		b.WriteString("\n\n")
+	}
 	b.WriteString("Use `!expedition status` for the daily briefing format. Day 1 begins now.")
 	return p.SendDM(ctx.Sender, b.String())
 }
 
+// raidContentWarning returns a TwinBee-voiced heads-up for zones whose
+// boss is tuned for a party rather than a solo adventurer. T5 zones
+// (Dragon's Lair / Abyss Portal) have boss HP / damage curves that the
+// solo combat path can't realistically clear — the J3 trace sweep at
+// L12 showed 0% solo clears across all 10 classes. Until multiplayer
+// expeditions ship, this is the surface that tells a player what
+// they're walking into without nerfing the encounter for parties later.
+func raidContentWarning(zoneID ZoneID) string {
+	switch zoneID {
+	case ZoneDragonsLair:
+		return "⚠ A note before we commit. Infernax doesn't go down to one sword. I've watched better-prepared adventurers walk in here and not walk back out, and I haven't yet seen the lone exception. Bring friends when you can. For tonight — I'm with you anyway."
+	case ZoneAbyssPortal:
+		return "⚠ A note before we commit. Belaxath is the kind of enemy you bring a band to. Not one solo hero has put him down yet, and I'd rather you weren't the first to try. We can still go. I just want the record to show I said this."
+	}
+	return ""
+}
+
 func estimateDays(maxSU, dailyBurn float32) int {
 	if dailyBurn <= 0 {
 		return 0