Fix Repo File Structure if Passthrough isn't Feasible

Currently the structure for this repository is causing issues with various helm commands and with our readme generation.

Since we have started a Big Bang wide effort to make sure we are making all of our charts pass-through wherever possible, we should first see if this is a feasible approach on this repository.

If it is not, then we will need to address the following:

1. Pull istiod and base folders out of chart/charts and into chart folder under the root directory
2. Update renovate.json to reference the updated file path
3. Update the references in the chart.yaml folder and add missing image reference under annotations section:

  helm.sh/images: | 
    - name: pilot
      image: registry1.dso.mil/ironbank/opensource/istio/pilot:1.25.1

4. Run helm dep update and validate helm template runs as expected and readme generation at the root works properly