Inconsistent treatment of **/ at end of Javadoc

After formatting, this:

```
public class DoubleTrailingAsterisk {

/**
* Here is a multi-line comment that ends with a double asterisk.
**/
public void m1() {}

/** Here is a single-line comment that ends with a double asterisk. **/
public void m2() {}
}
```

becomes this:

```
public class DoubleTrailingAsterisk {

/** Here is a multi-line comment that ends with a double asterisk. */
public void m1() {}

/** Here is a single-line comment that ends with a double asterisk. * */
public void m2() {}
}
```

where the second Javadoc comment contains an extra "*".

Reproduce the issue with the two Javadoc examples in the report and compare the formatted output. Trace the formatter's Javadoc-comment handling, then add a regression test showing that a single-line comment ending in **/ does not gain an extra asterisk; the existing examples should format consistently.

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