Support single host routing for DevWorkspace engine

[l0rd]

Is your enhancement related to a problem? Please describe.

Che configured to use the DevWorkspace as the workspace engine should use single host strategy. That means that workspaces editors/plugins get routed through the URL path (rather then the subdomain) and devfile components have their own URL sub-domain.

Describe the solution you'd like

• Support single host deployment in DevWorkspaces platform team
• validate that when deploying with engine set to devworkspace then it's possible start workspaces both based on devfile v1 and v2 (having both configured as single-host may be tricky and is not in the scope) platform team - deployment of devfile1 through che server and of devfile2 manually using kubectl works, factory links not tested due to lack of support on dashboard side

Subtask "che operator should deploy che-devworkspace-operator (along with devworkspace-operator) when instructed to do so" (#19142) is tracked in a distinct epic #19121.

[l0rd]

The subtask "che operator should deploy che-devworkspace-operator) is already tracked in the operator epic #19121. I am removing it as a subtask here and closing this epic as it looks like it was the only remaining task. Feel free to re-open if I am getting this wrong.