feat(scripts): add diagnostic, seed, and test scripts

- Add add-ai-provider-visibility and add-missing-columns migration scripts

- Add clear-error-book, seed-error-book, diagnose-error-book scripts

- Add diagnose-tables and create-missing-tables scripts

- Add test-failing-modules and test-teacher-pages test scripts

scripts/add-ai-provider-visibility.js

@@ -0,0 +1,118 @@
+/**
+ * V3: 为 ai_providers 表添加 visibility 列（public/private）
+ *
+ * 背景：
+ *   - 管理员可发布 public provider，全员可用
+ *   - 普通用户（teacher/student 等）可创建 private provider，仅本人可见
+ *
+ * 缺失列清单：
+ *   - ai_providers.visibility        (可见性：public | private，默认 private)
+ *   - 索引 ai_provider_visibility_idx (visibility)
+ *   - 索引 ai_provider_created_by_idx (created_by)
+ *
+ * 注意：默认值设为 'private'，保证历史记录不会意外对全员公开。
+ *      管理员可在 UI 中将需要共享的 provider 改为 public。
+ */
+require("dotenv/config");
+const mysql = require("mysql2/promise");
+
+const ALTER_OPERATIONS = [
+  {
+    table: "ai_providers",
+    description: "添加 visibility 列（public/private 可见性）",
+    sql: [
+      "ALTER TABLE `ai_providers` ADD COLUMN `visibility` ENUM('public','private') NOT NULL DEFAULT 'private' AFTER `is_default`",
+      "ALTER TABLE `ai_providers` ADD INDEX `ai_provider_visibility_idx` (`visibility`)",
+      "ALTER TABLE `ai_providers` ADD INDEX `ai_provider_created_by_idx` (`created_by`)",
+    ],
+  },
+];
+
+async function columnExists(conn, table, column) {
+  const [rows] = await conn.execute(
+    `SELECT COLUMN_NAME FROM information_schema.COLUMNS
+     WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = ? AND COLUMN_NAME = ?`,
+    [table, column],
+  );
+  return rows.length > 0;
+}
+
+async function indexExists(conn, table, indexName) {
+  const [rows] = await conn.execute(
+    `SELECT INDEX_NAME FROM information_schema.STATISTICS
+     WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = ? AND INDEX_NAME = ?
+     LIMIT 1`,
+    [table, indexName],
+  );
+  return rows.length > 0;
+}
+
+async function main() {
+  const conn = await mysql.createConnection({ uri: process.env.DATABASE_URL });
+  console.log("✅ 已连接数据库\n");
+
+  for (const op of ALTER_OPERATIONS) {
+    console.log(`${"=".repeat(60)}`);
+    console.log(`表: ${op.table} — ${op.description}`);
+    console.log("=".repeat(60));
+
+    for (const sql of op.sql) {
+      try {
+        const isColumn = sql.includes("ADD COLUMN");
+        const isIndex = sql.includes("ADD INDEX");
+
+        if (isColumn) {
+          const match = sql.match(/ADD COLUMN `(\w+)`/);
+          if (match && await columnExists(conn, op.table, match[1])) {
+            console.log(`  ⏭️  跳过已存在的列: ${match[1]}`);
+            continue;
+          }
+        } else if (isIndex) {
+          const match = sql.match(/ADD INDEX `(\w+)`/);
+          if (match && await indexExists(conn, op.table, match[1])) {
+            console.log(`  ⏭️  跳过已存在的索引: ${match[1]}`);
+            continue;
+          }
+        }
+
+        await conn.execute(sql);
+        console.log(`  ✅ 执行成功: ${sql.slice(0, 100)}...`);
+      } catch (err) {
+        if (err.code === "ER_DUP_FIELDNAME" || err.code === "ER_DUP_KEYNAME" || err.errno === 1060 || err.errno === 1061) {
+          console.log(`  ⏭️  已存在，跳过: ${err.message}`);
+        } else {
+          console.error(`  ❌ 执行失败: ${err.message}`);
+          console.error(`     SQL: ${sql}`);
+        }
+      }
+    }
+    console.log("");
+  }
+
+  // 验证最终列结构
+  console.log(`${"=".repeat(60)}`);
+  console.log("最终验证 — 检查 visibility 列是否已添加");
+  console.log("=".repeat(60));
+
+  const checks = [
+    ["ai_providers", "visibility"],
+  ];
+
+  let allOk = true;
+  for (const [table, col] of checks) {
+    const exists = await columnExists(conn, table, col);
+    const status = exists ? "✅" : "❌";
+    if (!exists) allOk = false;
+    console.log(`  ${status} ${table}.${col}`);
+  }
+
+  console.log(allOk ? "\n✅ visibility 列已就绪" : "\n❌ 仍有缺失列，请检查错误");
+
+  await conn.end();
+  process.exitCode = allOk ? 0 : 1;
+}
+
+main().catch((err) => {
+  console.error("致命错误:", err);
+  process.exit(1);
+});