Go to def on module params and module outputs should work with JSON files

This issue will become relevant once #3690 is merged.

The JSON semantic model has a `Template` object if the template is sufficiently valid. Inside the `Template` object, we should have location info for parameters and outputs (or at least some properties inside them), so this might not be that hard to implement.

Review prerequisite issue #3690 and the JSON semantic model, focusing on the Template object and its parameter and output locations. Confirm how valid templates expose these locations, then verify that Go to Definition resolves module parameters and outputs in JSON files.

Written by the indexing model from the issue text.