grid proxy: Index system resources

[SalmaElsoly]

for the favor of this issue codescalers/kubecloud#691 (comment)
We need to store the system resources and include them in the node data response

[SalmaElsoly]

work completed:

• update workload indexer to save system usage resources as well
• added new table to save system resource and trigger on insert/update to update node system resources fields
• added system resources field to node type

todo:

• testing

[SalmaElsoly]

update:

after discussion with @xmonader we agreed on:
1- indexing system resource with adding margin 10% from the system overhead
2- adding extra struct in node data avaliable_resources = total - system - used

[SalmaElsoly]

update:

• already system resources is included in used resources so there is no need for that anymore and will be handled in the frontend

[SalmaElsoly]

update:

populated system resources in node