Option to automatically migrate Windows workstations

[noahtalerman]

Goal

User story
As an IT admin,
I want to migrate my Windows workstations from my old MDM solution to Fleet
so that I can use Fleet to enforce disk encryption, OS updates, and other OS settings on these hosts.

Context

• Requestor(s): @dherder, @pintomi1989
• Product designer: @rachaelshaw

Pricing page language: An "on" button in Fleet so you have control over when Windows workstations switch.

Flip this behavior:

Edge cases to consider:

• What about offline hosts?
• What happens in between toggling?
• What about the folks that have ‘Windows MDM turned on’
• What happens to those fleetd enrolled Windows hosts?
• What does the reporting look like? (status of hosts that have not transitioned yet, and which have. What if some never check in? How will I know which have and which haven't?)

Changes

Product

• Reference documentation changes: TODO
• UI changes: Figma
• CLI (fleetctl) usage changes: TODO
• YAML changes: TODO
• REST API changes: TODO
• Fleet's agent (fleetd) changes: TODO
• Activity changes: TODO
• Permissions changes: TODO
• Changes to paid features or tiers: TODO

Engineering

• Feature guide changes: TODO
• Database schema migrations: TODO
• Load testing: TODO

ℹ️  Please read this issue carefully and understand it. Pay special attention to UI wireframes, especially "dev notes".

QA

Risk assessment

• Requires load testing: TODO
• Risk level: Low / High TODO
• Risk description: TODO

Manual testing steps

1. Step 1
2. Step 2
3. Step 3

Testing notes

Confirmation

1. Engineer (@____): Added comment to user story confirming successful completion of QA.
2. QA (@____): Added comment to user story confirming successful completion of QA.