v0.9.0 — an agent's queue belongs to the agent

There was one way to hold Salesforce cases to a single queue: COVEY_SALESFORCE_INTAKE_QUEUES, a process environment variable. That is the wrong scope for the thing it configures. Which queue somebody looks after is a property of the employee — two agents on one installation are the normal case, and an env var narrows both or neither.

The queue moves into the credential, beside the other per-agent components of salesforce_url:

salesforce_url = https://acme.my.salesforce.com queue="Support Tier 1"

The quotes are the reason splitComponents replaces strings.Fields: real queue names have spaces in them ("Digital Learning Support"), and a setting that cannot hold the value people actually have is a setting nobody uses. An unquoted name with a space now fails at the credential rather than silently becoming a queue called "Digital".