feat(simulation): add vision cone with forward/peripheral/blind sectors (#111)

Implement direction-dependent visibility modulation per D-015.
Forward cone (~120 deg) at full range, peripheral (~180 deg each side)
at reduced range, blind spot (~60 deg behind) excluded. Facing component
updated on player movement via facing_from_delta.

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

server/src/simulation/input.rs

@@ -3,6 +3,7 @@
 // PlayerInput: semantic actions (MoveNorth, Interact, UsePerceptionMode)
 
 use crate::bridge::types::{PlayerAction, PlayerInput};
+use crate::perception::vision_cone::{facing_from_delta, Facing};
 use crate::simulation::movement::{MoveIntent, PlayerCharacter, TilePosition};
 use crate::simulation::time::SimulationTime;
 use bevy_ecs::prelude::*;
@@ -101,6 +102,10 @@ fn apply_move(
         commands.entity(entity).insert(MoveIntent {
             target: TilePosition::new(pos.x + dx, pos.y + dy, pos.z),
         });
+        // Update facing direction based on movement (D-015 vision cone)
+        commands
+            .entity(entity)
+            .insert(Facing(facing_from_delta(dx, dy)));
     } else {
         tracing::warn!("No player entity found for movement input");
     }