Connected workspaces rewrites & updates for Beta release

[cwarnermm]

Docs Impact:

• New Connected Workspaces page replaces existing Shared Channels documentation.
• Existing config settings moved from Experimental to Site Configuration.
• New config settings added to Site Configuration

Documentation:

• Adds a feature flag to control availability of DMs in shared channels mattermost#28920
• MM-58349: Shared Channels in System Console mattermost#28116
• Adds ConnectedWorkspacesSettings configuration block mattermost#27820
• MM-58452-Update system console with shared indicator mattermost#28131
• 
MM-58451 Add/Update Shared Channel indicator locations mattermost#28130
• Adds status sync to shared channels mattermost#28020
• Adds a ConnectedWorkspaces.MaxPostsPerSync configuration property mattermost#28154

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA ec3c968

[cwarnermm]

@mgdelacroix - Please confirm whether the remote clusters configuration setting should remain documented as-is via Experimental, or if it needs changes for connected workspaces.

Also, please confirm whether any of the connected workspace configuration settings should be added to the Telemetry page.

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 46144f9

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 70818b1

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 1b38c80

[mgdelacroix]

Looking really good! Added a couple of change proposals and questions

[mgdelacroix]

Please confirm whether the remote clusters configuration setting should remain documented as-is via Experimental, or if it needs changes for connected workspaces.

We're maintaining those configuration parameters marked as deprecated, and they will have no effect beyond the initial automated migration to ConnectedWorkspaces the first time v10.2 runs, so I think we should mark them as deprecated in the experimental section and point to the new ones.

Also, please confirm whether any of the connected workspace configuration settings should be added to the Telemetry page.

Yes, all ConnectedWorkspaces properties have been added to the telemetry payload with the following format:

{
  "config_connected_workspaces": {
    "enable_shared_channels": val,
    "enable_remote_cluster_service": val,
    "disable_shared_channels_status_sync": val,
    "max_posts_per_sync": val
  }
}

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 9cf5844

[cwarnermm]

Thank you, @mgdelacroix, for your excellent review and input. I've incorporated your feedback in my last couple of commits. This docs PR is ready for your approval.

[github-actions]

Newest code from mattermost has been published to preview environment for Git SHA 4ffce02