refactor(simulation): split the input.rs and dialogue.rs dispatchers (T-1062)

input.rs 2,739 → 858 lines: per-domain action handlers moved to their
owning modules (inventory, movement, stance, examine, follow, interaction,
save_io, settings, bridge::debug, economy, vision_cone, bookmark,
test_world reset + new teleport.rs); input.rs keeps the queue, the thin
dispatch table, and pause/cooldown glue. All 9 type_complexity allows
dissolved via one PlayerInputQuery alias.

dialogue.rs → dialogue/ directory module: selection (631), response
(1,473), confrontation (714), mod.rs (226, shared session components +
re-exports — public paths preserved). Documented seam deviation:
process_walk_away lives with confrontation (D-064/D-063 share the same
world-response shape).

Mechanical, zero behavior change: determinism + golden_suite byte-identical
(independently re-verified); 1,504 lib tests unchanged — 23 input tests
moved with their subjects, 53 dialogue tests redistributed, zero deleted.
System scheduling registrations untouched (input_plugin.rs 0-line diff).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

server/src/simulation/follow.rs

@@ -239,6 +239,58 @@ pub fn update_follow_state(
     }
 }
 
+/// Handle Follow verb: designate an NPC as follow target (#241).
+/// Sets FollowTarget on the player entity. Replaces any existing follow target.
+/// Server-side range check: Follow requires CLOSE_RANGE (same as Talk).
+pub fn handle_follow(
+    commands: &mut Commands,
+    registry: &crate::knowledge::EntityRegistry,
+    player_query: &crate::simulation::input::PlayerInputQuery,
+    all_positions: &Query<&TilePosition>,
+    target_entity_id: Option<u64>,
+    current_tick: u64,
+) {
+    let Some(target_id) = target_entity_id else {
+        tracing::warn!("Follow verb without target_entity_id");
+        return;
+    };
+
+    let Ok((player_entity, player_pos, _, _)) = player_query.single() else {
+        return;
+    };
+
+    let target_stable = crate::knowledge::StableId(target_id);
+    let Some(target_entity) = registry.to_entity(&target_stable) else {
+        tracing::warn!(target_id, "Follow: target entity not in registry");
+        return;
+    };
+
+    // Server-side range check: reject Follow if target is beyond close range
+    if let Ok(target_pos) = all_positions.get(target_entity) {
+        let distance = player_pos
+            .manhattan_distance(target_pos)
+            .unwrap_or(u32::MAX);
+        if distance > crate::simulation::interaction::CLOSE_RANGE {
+            tracing::info!(
+                target_id,
+                distance,
+                "Follow: target out of range (max {})",
+                crate::simulation::interaction::CLOSE_RANGE,
+            );
+            return;
+        }
+    }
+
+    commands.entity(player_entity).insert(FollowTarget {
+        target: target_entity,
+        started_tick: current_tick,
+        proximity_ticks: 0,
+        los_lost_ticks: 0,
+    });
+
+    tracing::debug!(target_id, "Follow: FollowTarget set on player");
+}
+
 // ---------------------------------------------------------------------------
 // Tests
 // ---------------------------------------------------------------------------