Go: hashicorp/hcl models

[egregius313]

Added models for the github.com/hashicorp/hcl packages.

[Copilot]

Pull Request Overview

Adds CodeQL extension models for the HashiCorp HCL packages, enabling taint tracking and source/sink identification in hcl and hclsimple.

• Introduce package grouping entries for hcl1 and hclsimple
• Define sourceModel entries for Decode/DecodeFile methods
• Add sinkModel and summaryModel entries to capture file inputs and taint propagation

Comments suppressed due to low confidence (2)

go/ql/lib/ext/github.com.hashicorp.model.yml:13

• The sourceModel entry for hclsimple.DecodeFile uses Argument[2], but DecodeFile only has two parameters (index 0 for the file path and index 1 for the destination). Update this to Argument[0] to correctly model the file input.

      - ["group:hclsimple", "", False, "DecodeFile", "", "", "Argument[2]", "file", "manual"]

go/ql/lib/ext/github.com.hashicorp.model.yml:26

• The summaryModel entry for hclsimple.Decode references Argument[3], but Decode only takes two parameters (Argument[0] and Argument[1]). Verify the intended method and adjust the argument indices (or method name) to match the actual function signature.

      - ["group:hclsimple", "", False, "Decode", "", "", "Argument[1]", "Argument[3]", "taint", "manual"]