refactor standalone_resource

[SteveALee]

Standalone_resource layout includes code specific to users of it - namely Supplemental Guidance and Act rules.

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[SteveALee]

@shawna-slh Ready to merge - need to synchronise with other resources using standalone_resource template

• ACT Rules
• ARIA
• interactive lists x 3

[SteveALee]

Merged into #51