已完成迁移验收和清理。

删除全部 Node.js 后端、.mjs 测试、辅助脚本、package*.json、node_modules 和迁移对照工具。
浏览器前端保留并迁入 [Eis.Web/wwwroot](C:/Users/BI/Documents/EIS-dotnet/src/Eis.Web/wwwroot/index.html)，统一改为 .js 模块。
修复一个隐藏遗漏：.NET 仍依赖 schema.mjs，且 MySQL 结构解析可能被转义反引号截断。现已改为原生 [SQLite SQL](C:/Users/BI/Documents/EIS-dotnet/src/Eis.Infrastructure/Data/Schema.sqlite.sql) 和 [MySQL SQL](C:/Users/BI/Documents/EIS-dotnet/src/Eis.Infrastructure/Data/Schema.mysql.sql) 资源。
更新了 [DatabaseInitializer.cs](C:/Users/BI/Documents/EIS-dotnet/src/Eis.Infrastructure/Data/DatabaseInitializer.cs)、项目配置、README 和迁移文档。
data 目录和现有数据库未修改；测试仅使用系统临时 SQLite 数据库。

tests/Eis.Infrastructure.Tests/Data/DatabaseInitializerTests.cs

@@ -6,6 +6,29 @@ namespace Eis.Infrastructure.Tests.Data;
 
 public sealed class DatabaseInitializerTests
 {
+    [Fact]
+    public async Task EmbeddedSchemas_AreNativeSqlResources()
+    {
+        var assembly = typeof(DatabaseInitializer).Assembly;
+        var resourceNames = assembly.GetManifestResourceNames();
+        var sqliteName = Assert.Single(resourceNames, name => name.EndsWith("Schema.sqlite.sql", StringComparison.Ordinal));
+        var mysqlName = Assert.Single(resourceNames, name => name.EndsWith("Schema.mysql.sql", StringComparison.Ordinal));
+
+        var sqlite = await ReadResourceAsync(assembly, sqliteName);
+        var mysql = (await ReadResourceAsync(assembly, mysqlName)).ReplaceLineEndings("\n");
+        var mysqlStatements = mysql.Split(
+            "\n-- EIS-STATEMENT\n",
+            StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+
+        Assert.Contains("CREATE TABLE IF NOT EXISTS schema_metadata", sqlite, StringComparison.Ordinal);
+        Assert.DoesNotContain("export const", sqlite, StringComparison.Ordinal);
+        Assert.True(mysqlStatements.Length >= 30);
+        Assert.All(mysqlStatements, statement =>
+            Assert.StartsWith("CREATE TABLE IF NOT EXISTS", statement, StringComparison.Ordinal));
+        Assert.Contains("`separator` VARCHAR(10)", mysql, StringComparison.Ordinal);
+        Assert.DoesNotContain("export const", mysql, StringComparison.Ordinal);
+    }
+
     [Fact]
     public async Task InitializeAsync_CreatesFreshDatabaseAndIsIdempotent()
     {
@@ -49,4 +72,12 @@ public sealed class DatabaseInitializerTests
         command.CommandText = sql;
         return Convert.ToInt64(await command.ExecuteScalarAsync());
     }
+
+    private static async Task<string> ReadResourceAsync(System.Reflection.Assembly assembly, string name)
+    {
+        await using var stream = assembly.GetManifestResourceStream(name)
+                                 ?? throw new InvalidOperationException($"Missing resource: {name}");
+        using var reader = new StreamReader(stream);
+        return await reader.ReadToEndAsync();
+    }
 }