2.1.2: Explicitly constructed java.lang.String loses hashCode and equalsIgnoreCase

### Description

Methods on an explicitly constructed `java.lang.String` are unavailable in 2.1.2. The unchanged feature passes on 1.5.2. This concerns `Java.type` and `new`, rather than assuming that a native JavaScript string should expose Java-only methods.

The [2.1.2 migration guide](https://github.com/karatelabs/karate/blob/v2.1.2/docs/MIGRATION_GUIDE.md#java-interop) says existing Java interop patterns work unchanged. If this conversion is intentional, please clarify the supported way to retain Java String methods and document the migration.

### Steps to Reproduce

Place the official standalone JAR in an empty directory and save this as `repro.feature`:

```gherkin
Feature: Methods on explicitly constructed Java strings
Scenario: Java String hashCode remains callable
* def JavaString = Java.type('java.lang.String')
* def value = new JavaString('abc')
* match value.hashCode() == 96354

Scenario: Java String equalsIgnoreCase remains callable
* def JavaString = Java.type('java.lang.String')
* def value = new JavaString('ABC')
* match value.equalsIgnoreCase('abc') == true
```

Run `java -jar karate-2.1.2.jar run repro.feature`.

Compare with `java -jar karate-1.5.2.jar repro.feature`.

No browser, server, credentials or configuration file is required.

### Expected Behavior

`hashCode()` returns `96354`, and `equalsIgnoreCase('abc')` returns `true`.

### Actual Behavior

2.1.2 fails both scenarios:

```text
TypeError: value.hashCode is not a function
TypeError: value.equalsIgnoreCase is not a function
```

1.5.2 passes both scenarios using the same Java installation.

### Karate Version

2.1.2 standalone; comparison 1.5.2.

### Java Version

Oracle Java 24.0.2.

### Operating System

macOS ARM64.