feat(server): initialize Rust/bevy_ecs simulation server

Server boilerplate epic (276) complete. Establishes the Rust simulation
server foundation per D-020 (subprocess/IPC architecture).

Structure:
- bevy_ecs 0.18 + bevy_app 0.18, MessagePack serialization (rmp-serde)
- SimulationPlugin with deterministic resources: SimulationTime (D-031),
  SimRng (D-030), InputQueue (D-010)
- Core IPC types: ObserverSnapshot, PlayerInput, SimBridge trait (D-020)
- CauseChain production component for provenance tracking (D-030)
- SimulationTier types with LRU eviction support (D-026)
- NPC 10-axis model components (D-024)
- 15 tests: inline unit tests + integration smoke/serialization tests
- make ci-server passes (clippy, fmt, build, test)

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

server/src/perception/mod.rs

@@ -0,0 +1,16 @@
+// Perception module - Information boundary system
+// Implements D-010 principle 2: every piece of state is tagged with who knows it
+// Generates ObserverSnapshot for client rendering
+
+use bevy_app::prelude::*;
+
+/// Perception system plugin
+/// Manages information boundaries and observer snapshots
+pub struct PerceptionPlugin;
+
+impl Plugin for PerceptionPlugin {
+    fn build(&self, _app: &mut App) {
+        // Stub implementation - will be populated in phase 2
+        tracing::debug!("PerceptionPlugin initialized");
+    }
+}