No command palette option to sign in, and also no way to know that errors are occurring because you're not signed in.

**Describe the bug**
I had no idea I was able to sign in. Been dealing with this nonsense for over a year: #222

**To Reproduce**

1. Press Ctrl+Shift+P to open command palette
2. Type "github actions"
3. Observe that there is no sign in option.

There is an option called "focus on view" which does _then_ give you a sign in option.

**Expected behavior**

An option to sign in.

**Screenshots**

You can imagine.

**Extension Version**
`v0.27.0`

**Additional context**

Probably what happened (months ago)
- I open a yaml file.
- vscode tells me to install a recommended extension.
- it prompts me to log in so I can access my workflows.
- Of course I'm going to dismiss it immediately because I already have my yml file open and it's a popup. If it said "you will get spurious errors all over your yaml file" then I may have thought twice.

I feel like the error info on the "env" access should say "you need to be logged in" or something.

Start by tracing the command palette flow for “github actions” and the validation errors shown for env access. Done means users can discover a sign-in action from the relevant command palette context and unauthenticated errors clearly explain that signing in is required.

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