feat(myTischtennis): implement session restoration for browser automation login

- Enhanced the loginWithBrowserAutomation method to accept an options parameter for restoring a saved Playwright session, allowing users to bypass CAPTCHA if the session is still valid.
- Added a new playwrightStorageState field in the MyTischtennis model to store the encrypted browser storage state, facilitating session persistence.
- Updated myTischtennisService to utilize the saved storage state during login attempts, improving user experience by reducing unnecessary CAPTCHA challenges.

backend/models/MyTischtennis.js

@@ -199,6 +199,30 @@ const MyTischtennis = sequelize.define('MyTischtennis', {
     type: DataTypes.DATE,
     allowNull: true,
     field: 'last_update_ratings'
+  },
+  playwrightStorageState: {
+    // Encrypted JSON blob: full Playwright browser storage state (cookies + localStorage).
+    // Allows restoring a previous login session without a new CAPTCHA challenge.
+    type: DataTypes.TEXT('long'),
+    allowNull: true,
+    field: 'playwright_storage_state',
+    set(value) {
+      if (value === null || value === undefined) {
+        this.setDataValue('playwrightStorageState', null);
+      } else {
+        const jsonString = typeof value === 'string' ? value : JSON.stringify(value);
+        this.setDataValue('playwrightStorageState', encryptData(jsonString));
+      }
+    },
+    get() {
+      const encrypted = this.getDataValue('playwrightStorageState');
+      if (!encrypted) return null;
+      try {
+        return JSON.parse(decryptData(encrypted));
+      } catch (_e) {
+        return null;
+      }
+    }
   }
 }, {
   underscored: true,