feat(boss): tint boss sprite outline by phase (P2 green, P3 red)

Add FlashSprite.setOutlineByBossPhase with light/dark green shade option and red fallback; BossPhaseSystem drives HeroViewComp.applyBossPhaseOutline directly after phase switch (MON faction, no hero-level event semantics, pool-node safe); extract getFlashSprite/applyOutlineByLevel to dedupe the three outline call sites.

assets/script/game/hero/hit-flash-white/scripts/FlashSprite.ts

@@ -10,6 +10,12 @@ export class FlashSprite extends Component {
     @property({ type: Material, tooltip: '绿色描边材质(2级)' })
     outlineMatGreen: Material | null = null;
 
+    @property({ type: Material, tooltip: '淡绿描边材质(Boss阶段2)' })
+    outlineMatGreenLight: Material | null = null;
+
+    @property({ type: Material, tooltip: '深绿描边材质(Boss阶段2备选)' })
+    outlineMatGreenDark: Material | null = null;
+
     @property({ type: Material, tooltip: '蓝色描边材质(3级)' })
     outlineMatBlue: Material | null = null;
 
@@ -19,6 +25,9 @@ export class FlashSprite extends Component {
     @property({ type: Material, tooltip: '黄色描边材质(5级)' })
     outlineMatYellow: Material | null = null;
 
+    @property({ type: Material, tooltip: '红色描边材质(Boss阶段3)' })
+    outlineMatRed: Material | null = null;
+
     orginalFlashMaterial: Material | null = null;
     defaultMaterial: Material | null = null; // 缓存最原始的无描边材质
     sprite: Sprite | null = null;
@@ -64,6 +73,37 @@ export class FlashSprite extends Component {
         }
     }
 
+    /**
+     * 按 Boss 阶段设置描边材质（优先级高于等级描边）
+     * Why: Boss 阶段是战斗强反馈（绿色警告 / 红色危险），与英雄等级成长是两套视觉语言，
+     *      用独立通道避免污染 setOutlineByLevel 的等级语义
+     * @param phase 阶段索引：1=P2 绿 / 2=P3 红 / 0=P1 恢复默认
+     * @param greenShade P2 绿色色调：'light' 淡绿（默认）/ 'dark' 深绿
+     */
+    public setOutlineByBossPhase(phase: number, greenShade: 'light' | 'dark' = 'light') {
+        if (!this.sprite) {
+            this.sprite = this.node.getComponent(Sprite);
+        }
+        if (!this.sprite) return;
+
+        let targetMat: Material | null = null;
+        if (phase === 1) {
+            targetMat = greenShade === 'dark'
+                ? (this.outlineMatGreenDark ?? this.outlineMatGreenLight ?? this.outlineMatGreen)
+                : (this.outlineMatGreenLight ?? this.outlineMatGreenDark ?? this.outlineMatGreen);
+        } else if (phase >= 2) {
+            targetMat = this.outlineMatRed ?? this.outlineMatYellow;
+        } else {
+            targetMat = this.defaultMaterial;
+        }
+
+        if (targetMat) {
+            // 更新基础材质，确保闪白结束后恢复到这个阶段描边材质
+            this.orginalFlashMaterial = targetMat;
+            this.sprite.setSharedMaterial(targetMat, 0);
+        }
+    }
+
     public clickFlash() {
         if (!this.sprite || !this.hitFlashMaterial) return;