Fix!: depend on all attributes of dbt model when passed to a macro

[georgesittas]

When we pass the dbt model keyword to a macro (e.g., {{ foo(model) }}), we can't easily track the attributes that are actually used, because the argument may be aliased and hence tracking actual uses of model requires a proper data flow analysis.

This PR handles this case by conservatively including all of model's supported attributes if a "standalone" reference is detected. We decided to exclude raw_code to reduce the snapshot's payload size, since we can access it through the JinjaQuery node directly.

P.S.: may need to revisit before merging to see if we can migrate this properly.