Release v0.1.0

Added / 新增

• Initial release of flutter_rtc_link: a Flutter plugin for real-time audio/video and IoT device management with a dual-engine architecture (WhipWhepEngine over flutter_webrtc, LiveKitEngine over livekit_client) behind one unified abstraction (RtcEngine / RtcSession / LocalPublisher / RemoteSubscriber).
  • flutter_rtc_link 首个版本：实时音视频 + 物联网设备管理插件，双引擎架构（基于 flutter_webrtc 的 WhipWhepEngine 与基于 livekit_client 的 LiveKitEngine）统一抽象（RtcEngine / RtcSession / LocalPublisher / RemoteSubscriber）。
• Lead-operator publishing with simulcast: startCamera / startMic / startScreenShare, zero-renegotiation switchCamera via replaceTrack (RFC 9725 friendly), and setPublishClarity that caps the top simulcast layer.
  • 牵头操作者推流（simulcast 多层）：startCamera / startMic / startScreenShare、经 replaceTrack 的零重协商 switchCamera（符合 RFC 9725），以及只限制最高层的 setPublishClarity。
• Subscription and picture switching: WHEP playback, per-stream RemoteSubscriber.setClarity, and a pure-Dart VideoGridController (main/pip/grid layouts, max visible, global clarity).
  • 订阅与画面切换：WHEP 拉流、每路独立的 RemoteSubscriber.setClarity，以及纯 Dart 的 VideoGridController（主画面 / 画中画 / 网格布局、最大可见数、全局清晰度）。
• Live relay: RoleTransfer.promote / handover (identity handover) and StreamRelay.toRtmp / cascade (server-side Egress or secondary WHIP push).
  • 直播转接：RoleTransfer.promote / handover（身份交接）与 StreamRelay.toRtmp / cascade（服务端 Egress 或二次 WHIP 推流）。
• Robot teleoperation: RobotController with joystick velocity integration, PTZ, telemetry, voice intercom hookup, and a 500 ms watchdog that auto-stops the robot on command timeout or link loss.
  • 机器人远控：RobotController 支持摇杆速度积分、云台 PTZ、遥测、语音对讲接入，以及指令超时 / 断链 500ms 内自动停车的看门狗保护。
• IoT device management suite: multi-channel DeviceProvisioning (BLE → DPP/QR → NFC → SoftAP → SmartConfig strategy chain with automatic degradation), OtaUpdater (BLE/HTTP with SHA-256 verification), DeviceLogCollector (local cache + batch upload), and Diagnostics (WebRTC stats + network probe + device logs → JSON/Markdown report).
  • 物联网设备管理四件套：多通道 DeviceProvisioning（BLE → DPP/QR → NFC → SoftAP → SmartConfig 策略链，失败自动降级）、OtaUpdater（BLE/HTTP，SHA-256 校验）、DeviceLogCollector（本地缓存 + 批量补传）、Diagnostics（WebRTC stats + 网络探测 + 设备日志 → JSON/Markdown 报告）。
• Unified permission gate RtcPermissions.requestAll(capabilities) covering the Android 13/14+ and iOS pitfalls (foreground-service microphone, nearby Wi-Fi devices, NFC entitlement); denials degrade features and emit RtcEvent.permissionDenied instead of crashing.
  • 统一权限入口 RtcPermissions.requestAll(capabilities)，覆盖 Android 13/14+ 与 iOS 的权限坑（前台服务麦克风、附近 Wi-Fi 设备、NFC entitlement）；权限被拒时功能降级并上报 RtcEvent.permissionDenied，不崩溃。
• Native modules: Android DPP (Wi-Fi Easy Connect) platform channel and a microphone foreground service; iOS Swift method-channel stub. Method channel prefix pkg.flutter.dev/rtc_link/ with centralized RtcErrorCodes.
  • 原生模块：Android DPP（Wi-Fi Easy Connect）平台通道与麦克风前台服务；iOS Swift method channel 桩。Method channel 前缀 pkg.flutter.dev/rtc_link/，错误码集中定义于 RtcErrorCodes。
• Ready-to-run example app (publish/subscribe, robot joystick, device management demos) and unit tests for the layout, clarity, relay, watchdog, provisioning, log-cache and diagnostics paths.
  • 可直接运行的 example 应用（推流 / 订阅、机器人摇杆、设备管理演示）以及布局、清晰度、转接、看门狗、配网、日志缓存与诊断路径的单元测试。
• Resilience layer for overseas / cross-public-network links: ResilientSession (supervised connect, jittered backoff reconnect with automatic re-subscription), RelayPlanner (per-region TURN ordering + RelayMode.forced escalation for CGNAT / cross-border paths), NetworkPathMonitor (Wi-Fi ↔ cellular handover → ICE restart) and MediaHealthMonitor (stutter / congestion / frozen-picture detection with keyframe → downgrade → re-subscribe recovery).
  • 面向海外 / 跨公网链路的韧性层：ResilientSession（受控建链、带抖动退避重连并自动重新订阅）、RelayPlanner（按区域排序 TURN + 面向 CGNAT / 跨境路径的 RelayMode.forced 升级）、NetworkPathMonitor（Wi-Fi ↔ 蜂窝切换触发 ICE 重启）与 MediaHealthMonitor（卡顿 / 拥塞 / 画面冻结检测，并按请求关键帧 → 降档 → 重建订阅逐级恢复）。
• App-side pause/resume confirmation flow: PauseResumeGate stamps every operation with an epoch; pausing bumps the epoch so buffered operations are dropped instead of replayed, and resuming is a two-step ticket handshake (requestResume → confirmResume) that expires. EpochOperationQueue adds latest-wins buffering for teleoperation.
  • 应用侧暂停 / 恢复确认流程：PauseResumeGate 为每个操作盖上 epoch 戳；暂停会递增 epoch，使缓存操作被丢弃而非补发；恢复是一次会过期的两步票据握手（requestResume → confirmResume）。EpochOperationQueue 为遥控提供"最新者胜"缓冲。
• Low-latency control link helpers: ControlLinkRouter (data channel preferred, MQTT fallback, latency budget), ControlRttTracker and CommandRateLimiter.
  • 低时延控制链路辅助：ControlLinkRouter（优先数据通道、回退 MQTT、带时延预算）、ControlRttTracker 与 CommandRateLimiter。
• AppLifecycleGate: maps Flutter lifecycle states (paused / hidden / detached) to background suspension and drives the pause/resume gate.
  • AppLifecycleGate：把 Flutter 生命周期状态（paused / hidden / detached）映射为后台暂停，并驱动暂停 / 恢复门。

Changed / 变更

• RobotController accepts an optional PauseResumeGate and CommandRateLimiter; pause() stops the robot immediately and invalidates every command issued before it, and the keepalive loop never replays a pre-pause velocity.
  • RobotController 可接收可选的 PauseResumeGate 与 CommandRateLimiter；pause() 立即停车并让此前所有指令失效，保活循环绝不补发暂停前的速度。
• WhipWhepSession implements IceRestartable: handover now rebuilds the peer connections with a fresh ICE configuration (WHIP/WHEP forbids renegotiation, RFC 9725).
  • WhipWhepSession 实现了 IceRestartable：切换时会用全新的 ICE 配置重建 peer connection（RFC 9725 规定 WHIP/WHEP 不可重协商）。