feat(pomodoro): Chronos 时间生物可视化（P0-P2）

- 新增 ChronosSphere 3D 生物主体：有机球体（顶点扰动）+ 粒子光环聚散 + 呼吸波纹环，useFrame 驱动与 tick 解耦
- 双风格深度定制：深潜（深海蓝绿冷光）/ 极光（紫青渐变），跟随 useSceneTheme 自动切换
- 六阶段状态色板：沉睡/呼吸/专注/短休/长休/濒临结束（最后 5 分钟暖色渐变）
- 接入普通视图（compact）与沉浸模式（full），可回退经典 TimerRing/ImmersiveRing（chronosEnabled 开关）
- 专注完成绽放动画：粒子爆发 + 波纹扩散（bloom 边沿触发）
- P2 守护灵联动：focusScore 驱动呼吸节奏/光效速度
- P2 环境光自适应：摄像头亮度采样（缺省关闭，隐私优先），暗环境自发光补偿
- P2 AI 规划师：PlannerBlock 本地节律规划（任务数 → 推荐时长 → 分组计划）
- 设置页新增「时间生物」区块与「今日下潜计划」
- 死代码清理：ChronosPhasePalette 导出降级为内部 interface

Author: Aparencia

client/src/features/pomodoro/components/ImmersiveTimer.tsx

@@ -17,6 +17,7 @@ import { useReducedMotion } from '@/hooks/useReducedMotion';
 import { BEAT } from '@/lib/animation/springConfig';
 import { useAudioPrefsStore } from '@/lib/audio/audioPrefsStore';
 import { AnchorReminderOverlay } from './AnchorReminderOverlay';
+import { ChronosCanvas } from './chronos/ChronosCanvas';
 import { ImmersiveRing } from './ImmersiveRing';
 import { ImmersiveControls } from './ImmersiveControls';
 import { useFlowMusic } from '@/hooks/useFlowMusic';
@@ -42,6 +43,12 @@ interface ImmersiveTimerProps {
   focusScore?: number;
   /** 3.8 心流音乐引擎是否激活 */
   flowMusicEnabled?: boolean;
+  /** 专注完成绽放触发（Chronos 时间生物） */
+  bloom?: boolean;
+  /** 环境光亮度 0-1（P2 暗环境自发光补偿） */
+  ambientLight?: number;
+  /** Chronos 生物形态开关（缺省 true，关闭回退经典环） */
+  chronosEnabled?: boolean;
 }
 
 /** 3.13 具身学习休息活动列表 */
@@ -94,6 +101,9 @@ export default function ImmersiveTimer({
   lastSessionKeywords,
   focusScore = 0,
   flowMusicEnabled = false,
+  bloom = false,
+  ambientLight = 0.5,
+  chronosEnabled = true,
 }: ImmersiveTimerProps) {
   const prefersReduced = useReducedMotion();
 
@@ -137,7 +147,9 @@ export default function ImmersiveTimer({
     [progressPercent],
   );
 
-  // 呼吸动画参数 — 匹配 BEAT.x5 (600ms 周期 → 实际用6s完整呼吸)
+  const isBreak = phase === 'short_break' || phase === 'long_break';
+
+  // 经典环呼吸动画参数（chronosEnabled=false 时回退）
   const breatheAnimation = prefersReduced
     ? {}
     : {
@@ -149,8 +161,6 @@ export default function ImmersiveTimer({
         },
       };
 
-  const isBreak = phase === 'short_break' || phase === 'long_break';
-
   // 3.13 休息活动轮换索引
   const [activityIndex, setActivityIndex] = useState(0);
   useEffect(() => {
@@ -220,8 +230,23 @@ export default function ImmersiveTimer({
         </motion.div>
       )}
 
-      {/* 中央计时器区域 */}
-      <ImmersiveRing progress={progress} timeStr={timeStr} label={label} breatheAnimation={breatheAnimation} />
+      {/* 中央计时器区域 — Chronos 时间生物（可回退经典环） */}
+      {chronosEnabled ? (
+        <ChronosCanvas
+          mode="full"
+          phase={phase}
+          isRunning={isRunning}
+          remainingSeconds={remainingSeconds}
+          started
+          intensity={focusScore > 0 ? focusScore : 50}
+          ambientLight={ambientLight}
+          bloom={bloom}
+          timeStr={timeStr}
+          label={label}
+        />
+      ) : (
+        <ImmersiveRing progress={progress} timeStr={timeStr} label={label} breatheAnimation={breatheAnimation} />
+      )}
 
       {/* T2 记忆锚点提醒浮层 — work 阶段每 12 分钟一句话要点，15 秒自动消失 */}
       <AnchorReminderOverlay />

client/src/features/pomodoro/components/chronos/ChronosCanvas.tsx

@@ -0,0 +1,131 @@
+/**
+ * ChronosCanvas — 时间生物容器
+ *
+ * R3F Canvas 包裹 ChronosSphere，按主题自动切换双风格（深潜/极光）。
+ * 支持 full（沉浸全屏）与 compact（普通视图表盘尺寸）两种模式。
+ * prefersReducedMotion 时回退 2D 静态形态（颜色随阶段变化，无动画）。
+ *
+ * @ai-context: Chronos 时间生物渲染容器，替代 TimerRing / ImmersiveRing 视觉层。
+ */
+import { Canvas } from '@react-three/fiber';
+import { useReducedMotion } from 'framer-motion';
+import { useSceneTheme } from '@/lib/3d/hooks/useSceneTheme';
+import { CHRONOS_STYLES, CHRONOS_PHASES, toChronosPhase, type ChronosPhase } from './chronosStyles';
+import { ChronosSphere } from './ChronosSphere';
+
+interface ChronosCanvasProps {
+  /** full = 沉浸全屏；compact = 普通视图表盘尺寸 */
+  mode?: 'full' | 'compact';
+  phase: 'work' | 'short_break' | 'long_break';
+  isRunning: boolean;
+  remainingSeconds: number;
+  started: boolean;
+  /** 守护灵分心分数 0-100（可选，P2） */
+  intensity?: number;
+  /** 环境光亮度 0-1（可选，P2 暗环境自发光补偿） */
+  ambientLight?: number;
+  /** 完成绽放触发（P1） */
+  bloom?: boolean;
+  onTap?: () => void;
+  /** 中央显示内容（时间字符串） */
+  timeStr: string;
+  /** 中央显示标签（如 专注中） */
+  label: string;
+}
+
+/** 2D 静态回退形态（reduced motion / 极端低配） */
+function ChronosStatic({ phase, timeStr, label }: {
+  phase: ChronosPhase;
+  timeStr: string;
+  label: string;
+}) {
+  const phaseColor = CHRONOS_PHASES[phase].body;
+  return (
+    <div className="relative flex items-center justify-center w-full h-full">
+      {/* 静态光环 + 渐变球体 */}
+      <div
+        className="rounded-full"
+        style={{
+          width: 'min(60%, 240px)',
+          aspectRatio: '1',
+          background: `radial-gradient(circle at 35% 30%, ${phaseColor}66 0%, #0C152433 55%, transparent 75%)`,
+          border: `2px solid ${phaseColor}55`,
+          boxShadow: `0 0 40px ${phaseColor}33`,
+        }}
+      />
+      <div className="absolute inset-0 flex flex-col items-center justify-center pointer-events-none">
+        <span className="font-timer font-light tracking-tight leading-none text-text-primary" style={{ fontSize: 'clamp(2rem, 8vmin, 4.5rem)', fontVariantNumeric: 'tabular-nums' }}>
+          {timeStr}
+        </span>
+        <span className="text-[11px] mt-2 font-medium tracking-[0.15em] uppercase text-text-tertiary">
+          {label}
+        </span>
+      </div>
+    </div>
+  );
+}
+
+export function ChronosCanvas({
+  mode = 'full',
+  phase,
+  isRunning,
+  remainingSeconds,
+  started,
+  intensity,
+  ambientLight,
+  bloom,
+  onTap,
+  timeStr,
+  label,
+}: ChronosCanvasProps) {
+  const theme = useSceneTheme();
+  const reduced = useReducedMotion();
+  const style = CHRONOS_STYLES[theme];
+  const chronosPhase = toChronosPhase(phase, isRunning, remainingSeconds, started);
+
+  // 降级：减少动效偏好 → 2D 静态形态
+  if (reduced) {
+    return <ChronosStatic phase={chronosPhase} timeStr={timeStr} label={label} />;
+  }
+
+  return (
+    <div
+      className={mode === 'full'
+        ? 'absolute inset-0 flex items-center justify-center pointer-events-none'
+        : 'relative w-[clamp(150px,34vmin,280px)] h-[clamp(150px,34vmin,280px)] pointer-events-none'}
+      aria-label={`${label} ${timeStr}`}
+      role="timer"
+    >
+      <Canvas
+        camera={{ position: [0, 0, 4.2], fov: 45 }}
+        dpr={[1, 1.5]}
+        gl={{ antialias: true, alpha: true }}
+        className={mode === 'full' ? '!absolute inset-0' : ''}
+      >
+        <ambientLight intensity={0.6} />
+        <pointLight position={[3, 3, 4]} intensity={1.2} />
+        <pointLight position={[-3, -2, -3]} intensity={0.4} color={style.emissiveColor} />
+        <ChronosSphere
+          phase={chronosPhase}
+          style={style}
+          intensity={intensity}
+          ambientLight={ambientLight}
+          bloom={bloom}
+          onTap={onTap}
+        />
+      </Canvas>
+      {/* 中央数字（HTML 层，与 3D 叠加） */}
+      <div className="absolute inset-0 flex flex-col items-center justify-center pointer-events-none">
+        <span
+          className="font-timer font-light tracking-tight leading-none text-text-primary"
+          style={{ fontSize: mode === 'full' ? 'clamp(3rem, 9vmin, 6rem)' : 'clamp(1.75rem, 7vmin, 3.5rem)', fontVariantNumeric: 'tabular-nums' }}
+        >
+          {timeStr}
+        </span>
+        <span className="text-[11px] mt-2 font-medium tracking-[0.15em] uppercase text-text-tertiary">
+          {label}
+        </span>
+      </div>
+    </div>
+  );
+}