feat(simulation): wire Sprint 15 systems + protocol v13

Register all new systems in NpcPlugin and SimulationPlugin with correct
ordering constraints. Protocol bumped to v13: tell_state on VisibleEntity,
follow_state and PostConversationQueue on ObserverSnapshot, Follow verb
on VerbKind. Observer snapshot populates tell state from DerivedTellState
and follow state from FollowTarget. System ordering: tolerance after
mood, deviation after activity, tell after mood+deviation, follow after
visibility geometry, event monologue after conversations.

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

server/src/bridge/mod.rs

@@ -173,6 +173,11 @@ impl Plugin for BridgePlugin {
                         .after(crate::perception::anomaly::detect_anomalies),
                     crate::simulation::monologue::process_sprint_anomaly_monologue
                         .after(crate::simulation::monologue::trigger_recognition_monologue),
+                    crate::simulation::monologue::trigger_event_monologue
+                        .after(crate::simulation::monologue::process_sprint_anomaly_monologue)
+                        .after(crate::simulation::sound::collect_sound_events)
+                        .after(crate::simulation::conversation::run_npc_conversations)
+                        .after(crate::simulation::dialogue::process_walk_away),
                     crate::simulation::dialogue::process_talk_interaction
                         .after(crate::simulation::input::process_player_input),
                     crate::simulation::dialogue::process_walk_away
@@ -180,10 +185,14 @@ impl Plugin for BridgePlugin {
                         .after(crate::simulation::dialogue::process_talk_interaction),
                     crate::simulation::dialogue::process_confrontation_response
                         .after(crate::simulation::input::process_player_input),
+                    crate::simulation::follow::update_follow_state
+                        .after(crate::perception::observer::compute_visibility_geometry)
+                        .after(crate::simulation::movement::validate_movement)
+                        .before(crate::perception::observer::compute_observer_snapshot),
                     crate::perception::observer::compute_observer_snapshot
                         .after(crate::perception::observer::compute_visibility_geometry)
                         .after(crate::simulation::interaction::compute_nearby_interactions)
-                        .after(crate::simulation::monologue::process_sprint_anomaly_monologue)
+                        .after(crate::simulation::monologue::trigger_event_monologue)
                         .after(crate::simulation::dialogue::process_talk_interaction)
                         .after(crate::simulation::dialogue::process_confrontation_response)
                         .before(crate::simulation::time::advance_tick),

server/src/bridge/text_renderer.rs

@@ -240,6 +240,7 @@ mod tests {
                     visibility: VisibilitySector::Forward,
                     relationship: RelationshipState::Unknown,
                     observation: EntityVisibility::Visible,
+                    tell_state: None,
                 },
                 VisibleEntity {
                     entity_id: 100,
@@ -250,6 +251,7 @@ mod tests {
                     visibility: VisibilitySector::Forward,
                     relationship: RelationshipState::Known,
                     observation: EntityVisibility::Visible,
+                    tell_state: None,
                 },
                 VisibleEntity {
                     entity_id: 200,
@@ -260,6 +262,7 @@ mod tests {
                     visibility: VisibilitySector::Forward,
                     relationship: RelationshipState::Unknown,
                     observation: EntityVisibility::Visible,
+                    tell_state: None,
                 },
             ],
             visible_tiles: vec![VisibleTile {
@@ -302,6 +305,7 @@ mod tests {
             scan_events: vec![],
             conversation_events: vec![],
             conversation_ended: vec![],
+            follow_state: None,
             sound_events: vec![],
             rng_seed: None,
         }
@@ -431,6 +435,7 @@ mod tests {
             scan_events: vec![],
             conversation_events: vec![],
             conversation_ended: vec![],
+            follow_state: None,
             sound_events: vec![],
             rng_seed: None,
         };

server/src/bridge/types.rs

@@ -15,7 +15,7 @@ pub use crate::simulation::time::{DayPhase, TickRate};
 /// negotiation is unnecessary. Client should reject snapshots with version !=
 /// PROTOCOL_VERSION. New fields use #[serde(default)] only during the migration
 /// period, then the default is removed once both sides are updated.
-pub const PROTOCOL_VERSION: u8 = 12;
+pub const PROTOCOL_VERSION: u8 = 13;
 
 /// The ONLY data structure crossing the client-server boundary (D-020)
 /// Contains all information visible to the observer at a given tick.
@@ -32,6 +32,8 @@ pub const PROTOCOL_VERSION: u8 = 12;
 ///           rng_seed (#527, deterministic replay — completes WRONG button loop).
 /// v11 adds: zone_id on VisibleTile (#523, D-077 OQ-09 resolution + D-073 crossfade).
 /// v12 adds: conversation_events, conversation_ended (#247, D-078 NPC-to-NPC conversations).
+/// v13 adds: tell_state on VisibleEntity (#90, D-024 tell system — for future client use),
+///           follow_state (#241, follow mechanic HUD state).
 /// Future fields: ambient sound events, HUD state (D-020 expansion).
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct ObserverSnapshot {
@@ -98,6 +100,11 @@ pub struct ObserverSnapshot {
     /// Client dismisses the passive dialogue panel for these pairs.
     #[serde(default)]
     pub conversation_ended: Vec<crate::simulation::conversation::ConversationEndEvent>,
+    /// Follow-mode state for client HUD display (#241).
+    /// Present when the player is actively following an NPC.
+    /// Client shows follow indicator with distance, LOS, and tension.
+    #[serde(default)]
+    pub follow_state: Option<crate::simulation::follow::FollowStateWire>,
     /// RNG seed active at this tick for deterministic replay (#527).
     /// The WRONG button writes this to seed.txt so replays reproduce observed bugs.
     /// None when the RNG resource is unavailable (should not occur in practice).
@@ -270,6 +277,11 @@ pub struct VisibleEntity {
     /// Visible = in LOS right now. Remembered = known but not in LOS.
     #[serde(default)]
     pub observation: EntityVisibility,
+    /// Current observable tell category for NPC entities (#90, D-024).
+    /// None for non-NPC entities or NPCs with no active tell this tick.
+    /// v0.1: field is emitted for future client use; client may ignore.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub tell_state: Option<crate::npc::tell_state::TellCategory>,
 }
 
 /// Category of visible entity
@@ -452,6 +464,12 @@ pub enum VerbKind {
     /// Furniture — sit/use
     Sit,
 
+    // --- NPC extended verbs ---
+    /// Follow an NPC — designate as follow target (#241).
+    /// Close range only. Enters follow mode: server tracks distance, LOS,
+    /// and NPC suspicion. Replaces previous follow target if any.
+    Follow,
+
     // --- Phase 2 verbs (observer, KG-gated, #422) ---
     /// Confront an NPC about known facts/contradictions.
     /// Phase 2 only: injected when observer has KnowsDetails+ confidence.