Getter with side-effect mutation in AbstractEarModule.getBundleDir() and getLibDir()

## Description

In `AbstractEarModule.java:240-251`, the getters `getBundleDir()` and `getLibDir()` silently mutate instance state:

```java
public String getBundleDir() {
bundleDir = cleanArchivePath(bundleDir); // modifies field
return bundleDir;
}
public String getLibDir() {
libDirectory = cleanArchivePath(libDirectory);
return libDirectory;
}
```

Getters modifying instance fields is surprising and makes debugging harder. While `cleanArchivePath` is idempotent, the side-effect could cause subtle bugs if a subclass overrides `getBundleDir()` while the parent field gets modified elsewhere.

## Expected behavior

Use a local variable instead of assigning to the field:

```java
public String getBundleDir() {
return cleanArchivePath(bundleDir);
}
```

Start in AbstractEarModule.java:240-251 and inspect getBundleDir() and getLibDir(), along with cleanArchivePath(). Done means both getters return the cleaned field value without assigning back to instance state; check the existing project tests afterward for regressions.

Written by the indexing model from the issue text.