Adv 2.0 D&D Phase 11 D1a: zone registry + Tier 1 zones

Zone Infrastructure SUB-A: ZoneDefinition / ZoneTier / ZoneEnemy /
ZoneBoss / ZoneLootEntry types and dndZoneRegistry. Tier 1 zones
populated per gogobee_dungeon_zones.md §5: Goblin Warrens (T1, L1-3,
boss Grol the Unbroken CR3) and Crypt of Valdris (T1, L1-3, boss
Valdris the Unburied CR5, phase 2 at 50% HP).

Helpers: getZone, zonesForLevel (2-tier-above ceiling), zonesByTier,
allZones.

Bestiary additions for Tier 1 enemy rosters: goblin_sneak,
goblin_archer, hobgoblin_grunt, worg, goblin_shaman,
hobgoblin_warchief, zombie, shadow, specter, wight, flameskull, plus
the two zone bosses. Zombie AC bumped 8->10 to satisfy engine
TestBestiaryAllWellFormed minimum.

7 new tests covering registry presence, bestiary-ref resolution, boss
CR floor, level-tier gating, loot-chance bounds, room-count sanity,
elite flag presence, and tier->level-range alignment. Full plugin
suite green.

Also marks SUB3 done in gogobee_subclass_system.md (all 15 subclasses
through L15 shipped across SUB3a-d).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/plugin/dnd_zone_test.go

@@ -0,0 +1,122 @@
+package plugin
+
+import "testing"
+
+// Phase 11 D1a — zone registry tests. Validates that:
+//   1. Tier 1 zones are registered.
+//   2. All enemy/boss BestiaryID references resolve.
+//   3. Level gating (zonesForLevel) respects the 2-tier-above ceiling.
+//   4. Loot tables either have explicit drop chances in [0,1] or
+//      UniqueAlways set.
+
+func TestZoneRegistry_Tier1Present(t *testing.T) {
+	if _, ok := getZone(ZoneGoblinWarrens); !ok {
+		t.Fatal("Goblin Warrens not registered")
+	}
+	if _, ok := getZone(ZoneCryptValdris); !ok {
+		t.Fatal("Crypt of Valdris not registered")
+	}
+	t1 := zonesByTier(ZoneTierBeginner)
+	if len(t1) != 2 {
+		t.Fatalf("expected 2 Tier 1 zones, got %d", len(t1))
+	}
+}
+
+func TestZoneRegistry_BestiaryRefsResolve(t *testing.T) {
+	for _, z := range allZones() {
+		for _, e := range z.Enemies {
+			if _, ok := dndBestiary[e.BestiaryID]; !ok {
+				t.Errorf("zone %s enemy %s missing from bestiary", z.ID, e.BestiaryID)
+			}
+		}
+		if _, ok := dndBestiary[z.Boss.BestiaryID]; !ok {
+			t.Errorf("zone %s boss %s missing from bestiary", z.ID, z.Boss.BestiaryID)
+		}
+	}
+}
+
+func TestZoneRegistry_BossCRMatchesZoneTier(t *testing.T) {
+	// Sanity: boss CR should be at least at the high end of tier
+	// CR range. Tier 1 = CR 1/8–1 enemies, but boss is CR 3–5.
+	for _, z := range allZones() {
+		if z.Boss.CR < 1 {
+			t.Errorf("zone %s boss CR %.1f too low", z.ID, z.Boss.CR)
+		}
+	}
+}
+
+func TestZonesForLevel_TierGate(t *testing.T) {
+	// L1 player (tier 1): can reach tier 1+2=3. With only T1 zones
+	// registered in D1a, returns both.
+	got := zonesForLevel(1)
+	if len(got) != 2 {
+		t.Fatalf("L1 should see 2 T1 zones, got %d", len(got))
+	}
+	// L20 player should also see all zones (no upper cutoff).
+	got = zonesForLevel(20)
+	if len(got) < 2 {
+		t.Fatalf("L20 should see all zones, got %d", len(got))
+	}
+}
+
+func TestZoneRegistry_LootDropChances(t *testing.T) {
+	for _, z := range allZones() {
+		for _, l := range z.Loot {
+			if l.UniqueAlways {
+				continue
+			}
+			if l.DropChance <= 0 || l.DropChance > 1 {
+				t.Errorf("zone %s loot %s drop chance %.2f out of range",
+					z.ID, l.ItemID, l.DropChance)
+			}
+		}
+	}
+}
+
+func TestZoneRegistry_RoomCountSane(t *testing.T) {
+	for _, z := range allZones() {
+		if z.MinRooms < 5 || z.MaxRooms > 10 || z.MinRooms > z.MaxRooms {
+			t.Errorf("zone %s rooms %d-%d outside design (5-10, min<=max)",
+				z.ID, z.MinRooms, z.MaxRooms)
+		}
+	}
+}
+
+func TestZoneRegistry_ElitesFlagged(t *testing.T) {
+	// Each Tier 1 zone roster should contain at least one elite (per
+	// design doc each zone lists ELITE entries).
+	for _, z := range allZones() {
+		anyElite := false
+		for _, e := range z.Enemies {
+			if e.IsElite {
+				anyElite = true
+				break
+			}
+		}
+		if !anyElite {
+			t.Errorf("zone %s has no elite enemy", z.ID)
+		}
+	}
+}
+
+func TestZoneRegistry_LevelRangeMatchesTier(t *testing.T) {
+	// Tier→expected level range per design doc §2.
+	expected := map[ZoneTier][2]int{
+		ZoneTierBeginner:   {1, 3},
+		ZoneTierApprentice: {3, 5},
+		ZoneTierJourneyman: {5, 8},
+		ZoneTierVeteran:    {8, 12},
+		ZoneTierLegendary:  {12, 20},
+	}
+	for _, z := range allZones() {
+		want, ok := expected[z.Tier]
+		if !ok {
+			t.Errorf("zone %s has unknown tier %d", z.ID, z.Tier)
+			continue
+		}
+		if z.LevelMin < want[0] || z.LevelMax > want[1] {
+			t.Errorf("zone %s level %d-%d outside tier %d range %d-%d",
+				z.ID, z.LevelMin, z.LevelMax, z.Tier, want[0], want[1])
+		}
+	}
+}