🐛 fix(sqlserver): 修复对象 SQL 定义获取失败

- SQL Server 对象定义改为通过 sys.all_sql_modules 按库、schema、对象名精确查询
- 增加 sp_helptext 兼容候选，支持拼接多行 Text 返回完整定义
- 统一修复视图、函数/存储过程、触发器定义查看与对象修改入口
- 补充 SQL Server 对象定义查询和组件回归测试

frontend/src/utils/sqlServerObjectDefinition.ts

@@ -0,0 +1,81 @@
+import { splitQualifiedNameSegments } from './qualifiedName';
+
+export type SqlServerObjectDefinitionKind = 'view' | 'routine' | 'trigger';
+
+const SQL_SERVER_OBJECT_TYPES: Record<SqlServerObjectDefinitionKind, string[]> = {
+  view: ['V'],
+  routine: ['P', 'PC', 'RF', 'FN', 'FS', 'FT', 'IF', 'TF'],
+  trigger: ['TR', 'TA'],
+};
+
+const escapeSqlServerLiteral = (raw: string): string => String(raw || '').replace(/'/g, "''");
+
+const quoteSqlServerIdentifier = (raw: string): string => `[${String(raw || '').replace(/]/g, ']]')}]`;
+
+const buildSqlServerObjectRef = (schemaName: string, objectName: string): string => {
+  const object = String(objectName || '').trim();
+  const schema = String(schemaName || '').trim();
+  if (!object) return '';
+  if (!schema) return object;
+  return `${quoteSqlServerIdentifier(schema)}.${quoteSqlServerIdentifier(object)}`;
+};
+
+const resolveSqlServerObjectTarget = (rawObjectName: string, fallbackDbName: string) => {
+  const segments = splitQualifiedNameSegments(rawObjectName).filter(Boolean);
+  const objectName = String(segments[segments.length - 1] || '').trim();
+  let schemaName = '';
+  let databaseName = String(fallbackDbName || '').trim();
+
+  if (segments.length >= 3) {
+    databaseName = String(segments[segments.length - 3] || databaseName).trim();
+    schemaName = String(segments[segments.length - 2] || '').trim();
+  } else if (segments.length === 2) {
+    schemaName = String(segments[0] || '').trim();
+  }
+
+  return { databaseName, schemaName, objectName };
+};
+
+export const buildSqlServerObjectDefinitionQueries = (
+  kind: SqlServerObjectDefinitionKind,
+  objectName: string,
+  dbName: string,
+  resultAlias: string,
+): string[] => {
+  const target = resolveSqlServerObjectTarget(objectName, dbName);
+  if (!target.objectName) return [];
+
+  const catalogPrefix = target.databaseName ? `${quoteSqlServerIdentifier(target.databaseName)}.` : '';
+  const safeObjectName = escapeSqlServerLiteral(target.objectName);
+  const safeSchemaName = escapeSqlServerLiteral(target.schemaName);
+  const objectTypes = SQL_SERVER_OBJECT_TYPES[kind] || [];
+  const typeFilter = objectTypes.length > 0
+    ? `  AND o.type IN (${objectTypes.map((type) => `'${type}'`).join(', ')})\n`
+    : '';
+  const schemaFilter = target.schemaName
+    ? `  AND s.name = N'${safeSchemaName}'\n`
+    : '';
+  const schemaOrder = target.schemaName
+    ? 's.name'
+    : "CASE WHEN s.name = N'dbo' THEN 0 WHEN s.name = N'sys' THEN 1 ELSE 2 END, s.name";
+
+  const moduleQuery = [
+    `SELECT TOP (1)`,
+    `    m.definition AS ${resultAlias}`,
+    `FROM ${catalogPrefix}sys.all_sql_modules AS m`,
+    `JOIN ${catalogPrefix}sys.all_objects AS o ON o.object_id = m.object_id`,
+    `JOIN ${catalogPrefix}sys.schemas AS s ON s.schema_id = o.schema_id`,
+    `WHERE o.name = N'${safeObjectName}'`,
+    typeFilter.trimEnd(),
+    schemaFilter.trimEnd(),
+    `  AND m.definition IS NOT NULL`,
+    `ORDER BY ${schemaOrder}, o.name`,
+  ].filter(Boolean).join('\n');
+
+  const objectRef = buildSqlServerObjectRef(target.schemaName, target.objectName);
+  const helpTextProcedure = target.databaseName
+    ? `EXEC ${quoteSqlServerIdentifier(target.databaseName)}.sys.sp_helptext @objname = N'${escapeSqlServerLiteral(objectRef)}'`
+    : `EXEC sys.sp_helptext @objname = N'${escapeSqlServerLiteral(objectRef)}'`;
+
+  return [moduleQuery, helpTextProcedure];
+};