Identify fields and tags in the transpiler

[jsternberg]

The transpiler will need to identify fields and tags so it knows when to create cursors and when the value will be included because it is a tag.

We will need to spec out a Schema interface and figure out how the schema is retrieved for the query.

Related to #94 and #112.

[stale]

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[stale]

This issue has been automatically closed because it has not had recent activity. Please reopen if this issue is still important to you. Thank you for your contributions.