[WIP] Map issue template metadata to NewIssue.md

[Copilot]

Plan: Map metadata from issue templates to NewIssue.md

• Understand current implementation

  • Review issue template parsing in getDataFromTemplate
  • Review IssueTemplate interface in util.ts
  • Review NewIssueFileOptions interface in issueFile.ts
  • Review makeNewIssueFile method in issueFeatureRegistrar.ts
  • Review template selection in createIssue method

• Implement changes to support labels and assignees in templates

  • Extend IssueTemplate interface to include labels and assignees
  • Update getDataFromTemplate method to parse labels and assignees from YAML frontmatter
  • Extend NewIssueFileOptions interface to include labels
  • Update createIssue method to pass template labels and assignees to options
  • Update makeNewIssueFile method to populate labels line with template labels
  • Update chooseTemplate return type to use IssueTemplate
  • Fix parseYamlTemplate to extract labels and assignees from YAML templates

• Test the changes

  • Build the extension
  • Test YAML parsing for different formats

• Run code review and security checks

  • Run code_review tool - No issues found
  • Run codeql_checker tool - No alerts found
  • Address feedback from @alexr00 about YAML parsing

Security Summary

No security vulnerabilities were discovered during the CodeQL security scan.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Map metadata from issue templates to NewIssue.md</issue_title>
<issue_description>

I have issue templates with metadata, e.g.:

---
name: Bug report
about: Report a bug, help us improve
title: A clear title describing the bug from a user's perspective
labels: bug, needs triage
assignees: username
---

[...some body...]

When I create a new issue using this template, the title is brought through, but the rest of the metadata is not included.

I.e. this is the generated NewIssue.md:

A brief title describing the bug from a user's perspective

Assignees: 
Labels: 
Milestone: 
Projects:

[...some body...]

Would be great to populate the metadata fields based on the issue template!</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Map metadata from issue templates to NewIssue.md #6212

---

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[alexr00]

@copilot The issue template is yml, which means we end up with extra yml characters like this:

Assignees: @- alexr000 
Labels: ["bug", "triage"] 

[Copilot]

@copilot The issue template is yml, which means we end up with extra yml characters like this:

Assignees: @- alexr000 ...

Fixed in 394a879. The parseYamlTemplate method now extracts labels and assignees from YAML issue templates as proper arrays, avoiding the extra YAML characters in the NewIssue.md output.