[Remote rendering 5.3] Remote mode deployment and pvserver packaging

### 📝 Description of the feature

Decide and implement how remote-mode VISOR is delivered so pvserver is available where it runs, rather than assumed present in the environment. This will be informed by the spike in 5.1

[Possible shape, if bundling pvserver into VISOR's Python package is not a good option: container built on ParaView base with VISOR installed onto ParaView's Python environment]

### Acceptance Criteria

Remote-mode VISOR runs with pvserver available in its deployment, version-matched to the ParaView/VTK stack.
The delivery mechanism is decided and implemented.

### 💵 Business Value

_No response_

### 🔗 Useful links and references

_No response_

Start by reading the spike referenced in 5.1 and compare the proposed Python-package and ParaView-base container delivery approaches. Confirm where remote-mode VISOR is deployed and how pvserver is supplied, then verify that it is available there and version-matched to the ParaView/VTK stack.

Written by the indexing model from the issue text.