[BUG] AKS extension wipes/re-downloads valid content if navigating 'Back' in WAC. Have an option to keep if detected

**Title**: Have option in the AKS WAC extension to keep downloaded content

**Description**:
If navigating 'back' in the WAC extension for AKS, any previously downloaded content in the 'Azure Kubernetes Service' folder is wiped and re-downloaded. This is time consuming. Have the option to keep the content rather than wasting time when it is normally perfectly valid.

Start by reproducing the Back navigation in the AKS WAC extension and inspect how content in the “Azure Kubernetes Service” folder is handled during navigation. Done means previously valid downloaded content can be retained and Back no longer causes an unnecessary wipe and re-download.

Written by the indexing model from the issue text.