feat(simulation): wire NPC pool generation and authored triangle instantiation (#176, #188)

Production startup now spawns 23 Sova NPCs with EntanglementTag
(Flat/Intrigue) based on triangle_membership. Three-phase spawn:
entity creation, cross-reference resolution, and authored triangle
instantiation. Five triangles (3 ActiveFork, 2 PassiveTension per
D-087) with deterministic IDs via FNV-1a hashing.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/npc/mod.rs

@@ -152,6 +152,25 @@ pub enum DeviationTrigger {
     Confrontation,
 }
 
+// ---------------------------------------------------------------------------
+// Entanglement tag (D-029, #176)
+// ---------------------------------------------------------------------------
+
+/// Marks an NPC's narrative entanglement level (D-029).
+///
+/// - `Flat`: background population — no triangle involvement, minimal story role.
+/// - `Mundane`: has routines and personality but no active triangle membership.
+/// - `Intrigue`: participates in at least one triangle — drives narrative tension.
+///
+/// For authored NPCs: determined by YAML `triangle_membership` field.
+/// For procedural NPCs: assigned by the 30/50/20 ratio via SimRng.
+#[derive(Component, Debug, Clone, Copy, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub enum EntanglementTag {
+    Flat,
+    Mundane,
+    Intrigue,
+}
+
 // ---------------------------------------------------------------------------
 // Axis 1: Want (D-024)
 // ---------------------------------------------------------------------------