Add soure ranges to CST->AST errors

[john-h-kastner-aws]

Description of changes

Fix #465. Add source information to errors found durring CST to AST conversion.

For example, the underlined source snippet in this error message:

john:cedar $ cargo run check-parse <<<'permit(principal == My-User::"alice", action, resource);'
Error:   × failed to parse policy set
  ╰─▶ expected an entity uid or matching template slot, found a `+/-` expression
   ╭─[<stdin>:1:1]
 1 │ permit(principal == My-User::"alice", action, resource);
   ·                     ────────────────
   ╰────
  help: entity types and namespaces cannot use `+` or `-` characters -- perhaps try `_` or `::` instead?

Checklist for requesting a review

The change in this PR is (choose one, and delete the other options):

• A bug fix or other functionality change requiring a patch to cedar-policy.

I confirm that this PR (choose one, and delete the other options):

• Updates the "Unreleased" section of the CHANGELOG with a description of my change (required for major/minor version bumps).

I confirm that cedar-spec (choose one, and delete the other options):

• Does not require updates because my change does not impact the Cedar Dafny model or DRT

Disclaimer

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[shaobo-he-aws]

Should it updated after #470 is merged first?

[cdisselkoen]

@shaobo-he-aws asks

Should it updated after #470 is merged first?

I think this is more complicated/intricate than #470, so it makes sense to merge this first, and I will update #470 accordingly. (basically applying the transformation in #470 to all of the code introduced in this PR)