refactor: favor ctx passing instead of keeping field in struct

[bartoszmajsak]

What can be improved

istio-workspace/pkg/model/types.go

Lines 52 to 60 in 8217ff9

	type SessionContext struct {
	context.Context
	Name string
	Namespace string
	Route Route
	Client client.Client
	Log logr.Logger
	}

https://go.dev/blog/context-and-structs

Why

It's considered confusing and discouraged by golang team.