Expose all resource policy options to OPA policies

[lukehoban]

Currently, OPA policies are only handed the input properties of the resource in question, which is available via the input variable in the .rego file.

However, Pulumi Policies have access to a larger set of inputs from the AnalyzeRequest type - including the following in addition to input properties:

• type
• urn
• name
• options
• provider

Ideally, these would all be available to policy evaluation in addition to input properties.

We will need to understand whether we can/should introduce these via a breaking change to the existing input variable, or via a new source that can be referenced from the .rego policies.