Perf: Optimize nested each scope sync and add telemetry

CHANGELOG.md

@@ -1,5 +1,12 @@
 # CHANGELOG
 
+## v1.0.11 (2026-05-21)
+
+### 核心优化
+- **嵌套作用域同步**: 彻底重构了 `$each` 指令在节点复用时的上下文同步机制。现在复用节点会主动感知并合并父级作用域变量（`_ref`）的变更，解决了在虚拟滚动场景下嵌套 `$each` 数据不更新的严重 Bug。
+- **按需扫描机制**: 引入了变更感知逻辑，只有当迭代项引用变化或父级上下文变量变化时才触发子树扫描（`_scanTree`），大幅提升了复杂嵌套组件的滚动性能。
+- **性能遥测系统**: 在 `dom.js` 中内置了 `__statePerformanceTelemetry` 埋点，支持实时监控 `scanCount`（扫描）、`reuseCount`（复用）和 `moveCount`（DOM 移动）等核心指标，为极致性能调优提供数据支撑。
+
 ## v1.0.10 (2026-05-18)
 
 ### 修复

src/dom.js

@@ -126,13 +126,25 @@ export function _updateBinding(binding) {
 						// Reuse existing nodes
 						node._keyedNodes.delete(keyVal);
 						existingNodes.forEach(child => {
-							child._ref[indexName] = k;
+							if (window.__statePerformanceTelemetry) window.__statePerformanceTelemetry.reuseCount++;
-							// If data reference hasn't changed, skip heavy scan
+							let scopeChanged = false;
-							if (child._ref[asName] !== item) {
+							for (let key in node._ref) {
+								if (key === asName || key === indexName) continue;
+								if (child._ref[key] !== node._ref[key]) {
+									child._ref[key] = node._ref[key];
+									scopeChanged = true;
+								}
+							}
+							const indexChanged = child._ref[indexName] !== k;
+							if (indexChanged) child._ref[indexName] = k;
+							
+							if (child._ref[asName] !== item || scopeChanged) {
 								child._ref[asName] = item;
+								if (window.__statePerformanceTelemetry) window.__statePerformanceTelemetry.scanCount++;
 								_scanTree(child, { thisObj: node._thisObj, extendVars: child._ref });
 							} else if (node.parentNode.lastChild !== child) {
 								// Just move to the end to maintain order
+								if (window.__statePerformanceTelemetry) window.__statePerformanceTelemetry.moveCount++;
 								node.parentNode.insertBefore(child, node);
 							}
 						});