feat: 新增多语言配置并优化语言加载逻辑

1. 新增多个页面的中英文多语言词条，包括会员卡协议、积分商品、收银台等
2. 新增退款商品选择、微信支付、电子名片等页面的语言包
3. 优化lang.js语言加载逻辑，支持蛇形命名转换和多路径匹配，完善$lang调用兼容处理

common/js/lang.js

@@ -61,11 +61,35 @@ const SHARED_LANG_PACKS = [
 ];
 
 function toCamelCaseName(name) {
-	return String(name || '').replace(/-([a-z])/g, function(_, letter) {
+	return String(name || '').replace(/[-_]([a-z])/g, function(_, letter) {
 		return letter.toUpperCase();
 	});
 }
 
+function toSnakeCaseName(name) {
+	return String(name || '')
+		.replace(/([A-Z])/g, '_$1')
+		.replace(/-/g, '_')
+		.toLowerCase();
+}
+
+function buildLangPathCandidates(parts) {
+	const results = [];
+	function walk(index, current) {
+		if (index >= parts.length) {
+			const path = current.join('/');
+			if (!results.includes(path)) results.push(path);
+			return;
+		}
+		const raw = parts[index];
+		const snake = toSnakeCaseName(raw);
+		walk(index + 1, current.concat(raw));
+		if (snake !== raw) walk(index + 1, current.concat(snake));
+	}
+	walk(0, []);
+	return results;
+}
+
 function normalizeSharedLangPack(path, langData) {
 	if (!langData || typeof langData !== 'object') return {};
 
@@ -98,15 +122,96 @@ function normalizePageLangPack(path, langData) {
 	const segments = String(path).split('/').filter(Boolean);
 	if (!segments.length) return langData;
 
+	let leaf = langData;
+	let hasLeaf = true;
+	for (const segment of segments) {
+		const key = toCamelCaseName(segment);
+		if (leaf && typeof leaf === 'object' && !Array.isArray(leaf) && leaf[key] !== undefined) {
+			leaf = leaf[key];
+		} else {
+			hasLeaf = false;
+			break;
+		}
+	}
+
+	const lastSegment = toCamelCaseName(segments[segments.length - 1]);
+	const currentPageLeaf =
+		hasLeaf && leaf && typeof leaf === 'object' && !Array.isArray(leaf)
+			? leaf
+			: (langData[lastSegment] && typeof langData[lastSegment] === 'object' && !Array.isArray(langData[lastSegment]) ? langData[lastSegment] : langData);
+	let result = deepCloneLang(langData);
+	if (currentPageLeaf !== langData) {
+		// 部分语言包本身就是完整路径结构，如 { pay: { result: { title } } }。
+		// 页面内通常仍会调用 $lang('title') / $lang('xxx')，所以需要把当前页面 leaf
+		// 也展开到顶层，避免运行时出现缺失 key 警告。
+		result = deepMergeLang(deepCloneLang(currentPageLeaf), result);
+	}
+	if (!result[lastSegment]) {
+		// 兼容页面内按文件名命名空间调用的写法，如 point/goods_list 页面调用
+		// $lang('goods_list.searchPlaceholder')。
+		result[lastSegment] = deepCloneLang(currentPageLeaf);
+	}
+
 	let namespaced = {};
 	let cursor = namespaced;
 	for (let i = 0; i < segments.length; i++) {
 		const segment = toCamelCaseName(segments[i]);
-		cursor[segment] = i === segments.length - 1 ? deepCloneLang(langData) : {};
+		cursor[segment] = i === segments.length - 1 ? deepCloneLang(currentPageLeaf) : {};
 		cursor = cursor[segment];
 	}
 
-	return deepMergeLang(deepCloneLang(langData), namespaced);
+	return deepMergeLang(result, namespaced);
+}
+
+function tryResolveQualifiedPageField(locale, field) {
+	const arr = String(field || '').split('.');
+	if (arr.length < 3) return undefined;
+
+	for (let i = arr.length - 1; i >= 2; i--) {
+		const langPathCandidates = buildLangPathCandidates(arr.slice(0, i));
+		for (const langPath of langPathCandidates) {
+			const pack = normalizePageLangPack(langPath, loadLangPackSync(locale, langPath));
+			const value = resolveLangField(pack, arr);
+			if (value !== undefined) return value;
+		}
+	}
+	return undefined;
+}
+
+function resolveLangField(langData, arr) {
+	let temp = langData;
+	for (const key of arr) {
+		if (temp && typeof temp === 'object' && temp[key] !== undefined) {
+			temp = temp[key];
+		} else {
+			return undefined;
+		}
+	}
+	return typeof temp === 'string' ? temp : undefined;
+}
+
+function tryResolveLoadedPageField(locale, field) {
+	const arr = String(field || '').split('.');
+	if (!arr.length) return undefined;
+
+	let matchedValue;
+	let matchedCount = 0;
+	const prefix = `${locale}_`;
+	for (const cacheKey in loadedLangPacks) {
+		if (!Object.prototype.hasOwnProperty.call(loadedLangPacks, cacheKey)) continue;
+		if (cacheKey.indexOf(prefix) !== 0) continue;
+		const langPath = cacheKey.slice(prefix.length);
+		if (langPath === 'common' || SHARED_LANG_PACKS.includes(langPath)) continue;
+
+		const pack = normalizePageLangPack(langPath, loadedLangPacks[cacheKey]);
+		const value = resolveLangField(pack, arr);
+		if (value !== undefined) {
+			matchedValue = value;
+			matchedCount++;
+			if (matchedCount > 1) return undefined;
+		}
+	}
+	return matchedCount === 1 ? matchedValue : undefined;
 }
 
 // 清除所有语言缓存(切语言/切租户/远端覆写更新时调用)
@@ -848,6 +953,16 @@ export default {
 				value = (raw !== undefined && typeof raw === 'string') ? raw : field;
 			}
 
+			if (value === field && arr.length >= 3) {
+				const qualifiedValue = tryResolveQualifiedPageField(locale, field);
+				if (qualifiedValue !== undefined) value = qualifiedValue;
+			}
+
+			if (value === field && field !== 'title') {
+				const loadedPageValue = tryResolveLoadedPageField(locale, field);
+				if (loadedPageValue !== undefined) value = loadedPageValue;
+			}
+
 			// 将结果存入字段缓存(不含参数替换部分:参数每次可能不同)
 			_fieldResultCache[fieldCacheKey] = value;