docs: add Phase 8-2 networking status, spec, plan, and deferred items

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/DEFERRED.md

@@ -62,6 +62,14 @@
 - **raycast_all (다중 hit)** — 가장 가까운 hit만 반환.
 - **BVH 조기 종료 최적화** — 모든 리프 검사 후 최소 t 선택. front-to-back 순회 미구현.
 
+## Phase 8-2
+
+- **상태 동기화 (스냅샷)** — 미구현. 서버→클라이언트 월드 상태 전송.
+- **보간 / 예측** — 미구현. 클라이언트 측 스무딩.
+- **지연 보상** — 미구현. 서버 측 히트 판정 보정.
+- **신뢰성 계층** — 미구현. 패킷 재전송, 순서 보장.
+- **암호화 / 인증** — 미구현.
+
 ## Phase 8-1
 
 - **자동 내비메시 생성** — Recast 스타일 복셀화 미구현. 수동 정의만.

docs/STATUS.md

@@ -125,6 +125,13 @@
 - voltex_ai: A* pathfinding on triangle graph (center-point path)
 - voltex_ai: Steering behaviors (seek, flee, arrive, wander, follow_path)
 
+### Phase 8-2: Networking Foundation
+- voltex_net: Packet protocol (Connect, Accept, Disconnect, Ping, Pong, UserData)
+- voltex_net: Binary serialization/deserialization
+- voltex_net: Non-blocking UDP socket wrapper
+- voltex_net: NetServer (client management, broadcast)
+- voltex_net: NetClient (server connection, handshake)
+
 ## Crate 구조
 
 ```
@@ -136,10 +143,11 @@ crates/
 ├── voltex_asset     — Handle<T>, AssetStorage<T>, Assets
 ├── voltex_physics   — Collider, ContactPoint, BvhTree, RigidBody, detect_collisions, physics_step, raycast
 ├── voltex_audio     — AudioClip, WAV parser, mixing, WASAPI backend, AudioSystem, MixGroup, spatial
-└── voltex_ai        — NavMesh, A* pathfinding, steering behaviors
+├── voltex_ai        — NavMesh, A* pathfinding, steering behaviors
+└── voltex_net       — UDP packets, NetServer, NetClient
 ```
 
-## 테스트: 228개 전부 통과
+## 테스트: 236개 전부 통과
 
 - voltex_asset: 14
 - voltex_audio: 35 (audio_clip 2 + wav 5 + mixing 11 + audio_system 2 + spatial 8 + mix_group 7)
@@ -148,6 +156,7 @@ crates/
 - voltex_physics: 52 (collider 2 + narrow 11 + bvh 5 + collision 7 + rigid_body 3 + integrator 3 + solver 5 + ray 10 + raycast 6)
 - voltex_platform: 3
 - voltex_ai: 15 (navmesh 4 + pathfinding 5 + steering 6)
+- voltex_net: 8 (packet 7 + integration 1)
 - voltex_renderer: 33 (20 + SSGI 3 + RT 3 + bloom 3 + tonemap 4)
 
 ## Examples (11개)
@@ -164,7 +173,7 @@ crates/
 - audio_demo — 사인파 오디오 재생
 - deferred_demo — 디퍼드 렌더링 + 다중 포인트 라이트
 
-## 다음: Phase 8-2 (네트워킹) / 8-3 (스크립팅) / 8-4 (에디터) — Stretch Goal
+## 다음: Phase 8-3 (스크립팅) / 8-4 (에디터) — Stretch Goal
 
 스펙 참조: `docs/superpowers/specs/2026-03-24-voltex-engine-design.md`
 

docs/superpowers/plans/2026-03-25-phase8-2-networking.md

@@ -0,0 +1,43 @@
+# Phase 8-2: Networking Foundation Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** UDP 기반 클라이언트-서버 네트워킹 인프라 — 패킷 직렬화, 연결 핸드셰이크, 데이터 송수신
+
+**Architecture:** `voltex_net` crate 신규. 바이너리 패킷 프로토콜 + non-blocking UdpSocket 래퍼 + NetServer(클라이언트 관리) + NetClient(서버 연결). std::net만 사용.
+
+**Tech Stack:** Rust, std::net::UdpSocket
+
+**Spec:** `docs/superpowers/specs/2026-03-25-phase8-2-networking.md`
+
+---
+
+## Task 1: Crate + Packet 직렬화
+
+Create crate, packet.rs with Packet enum and binary serialization.
+
+- Cargo.toml: no dependencies
+- Workspace: add members + workspace.dependencies
+- Packet enum: Connect, Accept, Disconnect, Ping, Pong, UserData
+- Header: [type u8, payload_len u16 LE, reserved u8]
+- to_bytes(), from_bytes()
+- 6 tests: roundtrip per variant + invalid bytes error
+
+Commit: `feat(net): add voltex_net crate with packet serialization`
+
+## Task 2: NetSocket + NetServer + NetClient
+
+Create socket.rs, server.rs, client.rs with full networking.
+
+- NetSocket: bind(non-blocking), send_to, recv_from
+- ClientInfo, ServerEvent, NetServer: poll, broadcast, send_to_client
+- ClientEvent, NetClient: connect, poll, send, is_connected, disconnect
+- Tests: localhost handshake, UserData roundtrip, disconnect
+
+Commit: `feat(net): add UDP server/client with connection management`
+
+## Task 3: Documentation
+
+Update STATUS.md and DEFERRED.md.
+
+Commit: `docs: add Phase 8-2 networking status and deferred items`

docs/superpowers/specs/2026-03-25-phase8-2-networking.md

@@ -0,0 +1,174 @@
+# Phase 8-2: Networking Foundation — Design Spec
+
+## Overview
+
+`voltex_net` crate를 신규 생성한다. UDP 소켓 래핑, 패킷 직렬화, 클라이언트-서버 연결 관리를 구현한다.
+
+## Scope
+
+- 패킷 프로토콜 (Connect, Accept, Disconnect, Ping, Pong, UserData)
+- 바이너리 직렬화/역직렬화
+- Non-blocking UDP 소켓 래퍼
+- NetServer (클라이언트 관리, broadcast)
+- NetClient (서버 연결, 핸드셰이크)
+
+## Out of Scope
+
+- 상태 동기화 (스냅샷)
+- 보간 / 예측
+- 지연 보상
+- 신뢰성 계층 (재전송, 순서 보장)
+- 암호화 / 인증
+
+## Module Structure
+
+```
+crates/voltex_net/
+├── Cargo.toml
+└── src/
+    ├── lib.rs
+    ├── packet.rs    — Packet enum, to_bytes, from_bytes
+    ├── socket.rs    — NetSocket (UdpSocket wrapper)
+    ├── server.rs    — NetServer
+    └── client.rs    — NetClient
+```
+
+## Dependencies
+
+- 없음 (std::net::UdpSocket만 사용)
+
+## Types
+
+### Packet
+
+```rust
+#[derive(Debug, Clone, PartialEq)]
+pub enum Packet {
+    Connect { client_name: String },
+    Accept { client_id: u32 },
+    Disconnect { client_id: u32 },
+    Ping { timestamp: u64 },
+    Pong { timestamp: u64 },
+    UserData { client_id: u32, data: Vec<u8> },
+}
+```
+
+### 직렬화 포맷
+
+```
+[type: u8] [payload_len: u16 LE] [reserved: u8] [payload...]
+```
+
+Type IDs: Connect=1, Accept=2, Disconnect=3, Ping=4, Pong=5, UserData=6
+
+Payload encoding:
+- Connect: name_len(u16) + name_bytes
+- Accept: client_id(u32)
+- Disconnect: client_id(u32)
+- Ping/Pong: timestamp(u64)
+- UserData: client_id(u32) + data_len(u16) + data_bytes
+
+```rust
+impl Packet {
+    pub fn to_bytes(&self) -> Vec<u8>
+    pub fn from_bytes(data: &[u8]) -> Result<Packet, String>
+}
+```
+
+### NetSocket
+
+```rust
+pub struct NetSocket {
+    socket: UdpSocket,
+}
+```
+
+- `bind(addr: &str) -> Result<Self, String>` — bind + set_nonblocking(true)
+- `send_to(&self, packet: &Packet, addr: SocketAddr) -> Result<(), String>`
+- `recv_from(&self) -> Option<(Packet, SocketAddr)>` — None if WouldBlock
+
+### ClientInfo
+
+```rust
+pub struct ClientInfo {
+    pub id: u32,
+    pub addr: SocketAddr,
+    pub name: String,
+}
+```
+
+### NetServer
+
+```rust
+pub struct NetServer {
+    socket: NetSocket,
+    clients: HashMap<u32, ClientInfo>,
+    next_id: u32,
+}
+```
+
+- `new(addr: &str) -> Result<Self, String>`
+- `poll(&mut self) -> Vec<ServerEvent>` — process incoming packets
+- `broadcast(&self, packet: &Packet)` — send to all clients
+- `send_to_client(&self, client_id: u32, packet: &Packet)`
+- `clients(&self) -> &HashMap<u32, ClientInfo>`
+- `client_count(&self) -> usize`
+
+### ServerEvent
+
+```rust
+pub enum ServerEvent {
+    ClientConnected { client_id: u32, name: String },
+    ClientDisconnected { client_id: u32 },
+    PacketReceived { client_id: u32, packet: Packet },
+}
+```
+
+### NetClient
+
+```rust
+pub struct NetClient {
+    socket: NetSocket,
+    server_addr: SocketAddr,
+    client_id: Option<u32>,
+    name: String,
+}
+```
+
+- `new(local_addr: &str, server_addr: &str, name: &str) -> Result<Self, String>`
+- `connect(&self)` — send Connect packet
+- `poll(&mut self) -> Vec<ClientEvent>` — process incoming
+- `send(&self, packet: &Packet) -> Result<(), String>`
+- `is_connected(&self) -> bool`
+- `client_id(&self) -> Option<u32>`
+- `disconnect(&self)`
+
+### ClientEvent
+
+```rust
+pub enum ClientEvent {
+    Connected { client_id: u32 },
+    Disconnected,
+    PacketReceived { packet: Packet },
+}
+```
+
+## Test Plan
+
+### packet.rs
+- Connect 라운드트립
+- Accept 라운드트립
+- Disconnect 라운드트립
+- Ping/Pong 라운드트립
+- UserData 라운드트립
+- 잘못된 바이트 → 에러
+
+### socket.rs
+- localhost 바인드
+- send + recv 라운드트립
+
+### server.rs + client.rs (통합)
+- 서버 시작 + 클라이언트 연결 → Accept 수신
+- 다수 클라이언트 연결
+- 클라이언트 Disconnect → 서버에서 제거
+- UserData 송수신