init: ShowenV2 项目骨架 — 数字生命窗口平台

- core/ 跨平台内核骨架 (Plugin trait, Message, ServiceManager, Config)
- plugins/ 空桩 (video, http, ble, screen, wifi)
- PROGRESS.md 进度跟踪, TEAM.md 团队档案
- cargo check 零 warning 通过

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

src/core/message.rs

@@ -0,0 +1,75 @@
+use crate::core::config::AppConfig;
+use std::sync::Arc;
+
+/// 消息信封：包含来源、目的地、消息体
+pub struct Envelope {
+    pub from: &'static str,
+    pub to: Destination,
+    pub message: Message,
+}
+
+/// 消息目的地
+pub enum Destination {
+    /// 点对点发送给指定插件
+    Plugin(&'static str),
+    /// 广播给所有插件
+    Broadcast,
+    /// 发给管理层自身
+    Manager,
+}
+
+/// 所有插件间通信的类型安全消息
+pub enum Message {
+    // ── 播放控制 ──
+    PlayerCommand(PlayerCommand),
+    PlayerStatus(PlayerStatusData),
+    Trigger { name: String, value: String },
+    StateChanged { old_state: String, new_state: String },
+
+    // ── 屏幕管理 ──
+    ScreenLockRequest(bool),
+    CursorVisibility(bool),
+
+    // ── 网络 ──
+    WifiCommand(WifiCommand),
+    WifiResult(String),
+    WifiProvisioned { ssid: String, ip: String },
+
+    // ── 配置 ──
+    ConfigReloaded(Arc<AppConfig>),
+    ConfigReloadRequest,
+
+    // ── 系统 ──
+    Shutdown,
+    PluginReady(&'static str),
+
+    // ── 扩展（未来插件用） ──
+    Custom { kind: String, payload: String },
+}
+
+pub enum PlayerCommand {
+    Play,
+    Pause,
+    Next,
+    Previous,
+    Goto(usize),
+    ChangeScene(String),
+}
+
+#[derive(Debug, Clone, serde::Serialize)]
+pub struct PlayerStatusData {
+    pub running: bool,
+    pub paused: bool,
+    pub in_transition: bool,
+    pub current_index: usize,
+    pub playlist_length: usize,
+    pub current_video: Option<String>,
+}
+
+pub enum WifiCommand {
+    Scan,
+    Connect { ssid: String, password: String },
+    Status,
+    ApStart { ssid: String, password: String },
+    ApStop,
+}