第58批修复：

- 领地误删致命bug：AreaProtection 改用 userExistsIgnoreCase（SQL异常返回true，不误删）
- getConnection 自动重连：连接已关闭时重建，解决 SN/信誉同步 database connection closed
- userExists/userExistsIgnoreCase/userExistsStrict 改用 getConnection() 自动重连
- AI配置解析跳过诊断日志：findProviderUrl 返回 null 时输出具体供应商名和路径，便于排查 0个模型 问题

src/main/java/Sdf1_login/AIChatManager.java

@@ -274,7 +274,10 @@ public class AIChatManager {
             boolean isCustom = supplierConfig.has("baseurl");
             boolean isBuiltin = supplierConfig.has("供应商名字");
 
-            if (!isCustom && !isBuiltin) continue;
+            if (!isCustom && !isBuiltin) {
+                plugin.getLogger().info("[AI聊天] 配置跳过[" + key + "]: 既无baseurl也无供应商名字");
+                continue;
+            }
 
             String baseUrl;
             String apiKey = getStr(supplierConfig, "apikey");
@@ -286,9 +289,14 @@ public class AIChatManager {
             } else {
                 String providerName = getStr(supplierConfig, "供应商名字");
                 baseUrl = findProviderUrl(providerName);
+                if (baseUrl == null || baseUrl.isEmpty()) {
+                    plugin.getLogger().warning("[AI聊天] 配置跳过[" + key + "]: 内置供应商 '" + providerName + "' 在 供应商.json 中找不到URL");
+                    plugin.getLogger().warning("[AI聊天] 诊断: 请确认 供应商.json 中存在路径 '" + providerName + "'，且路径拼写完全正确");
+                }
             }
 
             if (baseUrl == null || baseUrl.isEmpty() || apiKey == null || apiKey.isEmpty()) {
+                plugin.getLogger().warning("[AI聊天] 配置跳过[" + key + "]: baseUrl=" + baseUrl + ", apiKey=" + apiKey);
                 continue;
             }
 

src/main/java/Sdf1_login/AreaProtection.java

@@ -10911,8 +10911,11 @@ public class AreaProtection implements Listener {
                     String reason = (String) o[1];
                     if (reason == null) {
                         if (dbMgr == null) continue;
+                        // ★ 第58批修复：SQL 异常时 userExists 返回 false，
+                        // 会把 DB 抖动误判为"账户已注销"从而删领地。
+                        // 改用 userExistsIgnoreCase（异常返回 true，宁可放过）。
                         try {
-                            if (!dbMgr.userExists(ac.owner)) {
+                            if (!dbMgr.userExistsIgnoreCase(ac.owner)) {
                                 reason = "账户已注销";
                             }
                         } catch (Exception ignored) {}

src/main/java/Sdf1_login/DatabaseManager.java

@@ -526,7 +526,24 @@ public class DatabaseManager {
         }
     }
 
+    /** 获取数据库连接，连接已关闭时自动重连。★ 第58批修复：避免 SN/信誉同步等模块拿到已关闭连接报 "database connection closed"。 */
     public Connection getConnection() {
+        try {
+            if (db == null || db.isClosed()) {
+                File dbDir = new File(dataFolder, "登录凭证");
+                dbDir.mkdirs();
+                File dbFile = new File(dbDir, "login.db");
+                db = DriverManager.getConnection(
+                        "jdbc:sqlite:" + dbFile.getAbsolutePath());
+                Statement st = db.createStatement();
+                st.execute("PRAGMA journal_mode=WAL");
+                st.execute("PRAGMA busy_timeout=5000");
+                st.close();
+                logger.warning("[Sdf1_login] 数据库连接已自动重建");
+            }
+        } catch (Exception e) {
+            logger.severe("[Sdf1_login] 数据库自动重连失败: " + e.getMessage());
+        }
         return db;
     }
 
@@ -704,7 +721,7 @@ public class DatabaseManager {
 
     public boolean userExists(String name) {
         try {
-            PreparedStatement ps = db.prepareStatement(
+            PreparedStatement ps = getConnection().prepareStatement(
                     "SELECT 1 FROM users "
                             + "WHERE player_name=?");
             ps.setString(1, name);
@@ -724,7 +741,7 @@ public class DatabaseManager {
     public boolean userExistsIgnoreCase(String name) {
         if (name == null || name.isEmpty()) return false;
         try {
-            PreparedStatement ps = db.prepareStatement(
+            PreparedStatement ps = getConnection().prepareStatement(
                     "SELECT 1 FROM users "
                             + "WHERE player_name=? "
                             + "COLLATE NOCASE");
@@ -747,7 +764,7 @@ public class DatabaseManager {
     public boolean userExistsStrict(String name) {
         if (name == null || name.isEmpty()) return false;
         try {
-            PreparedStatement ps = db.prepareStatement(
+            PreparedStatement ps = getConnection().prepareStatement(
                     "SELECT 1 FROM users "
                             + "WHERE player_name=? "
                             + "COLLATE NOCASE");