For #[26070](https://github.com/fleetdm/fleet/issues/26070)
This adds the UI for enabling a manual agent install for a bootstrap
package. This includes:
**The new form option for enabling manual agent install of a bootstrap
package**
**disabling adding install software and run script options when user has
enabled manual agent install**
**improvements to the setup experience content styling. I've created a
`SetupExperienceContentContainer` component to centralise the styles for
the content of these sub sections.**
**updates to the preview sections copy and replacing the gifs with
videos**
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
- [ ] Added/updated automated tests
- [x] Manual QA for all new/changed functionality
---------
Co-authored-by: Sarah Gillespie <73313222+gillespi314@users.noreply.github.com>
