Add JIRA Issue Properties API support

[Copilot]

Implementation Plan for JIRA Issue Properties API

• Review Jira Issue Properties API documentation and existing code patterns
• Create entity classes for Issue Properties responses
  • PropertyKeys entity for listing property keys
  • PropertyKey entity for individual key info
  • IssueProperty entity for full property value
• Add extension methods to IssueDomainExtensions.cs:
  • GetPropertyKeysAsync - Get all property keys for an issue
  • GetPropertyAsync - Get a specific property value
  • SetPropertyAsync - Set/update a property on an issue
  • DeletePropertyAsync - Delete a property from an issue
• Create comprehensive tests for all new methods
• Verify code builds successfully
• Resolve merge conflicts with master branch
• Run security checks with CodeQL (0 alerts found)
• Implementation complete and ready for review

Original prompt

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This section details on the original issue you should resolve

<issue_title>Add support for JIRA Issue Properties API</issue_title>
<issue_description>Add support for JIRA Issue Properties API to allow:

• Getting all properties for an issue
• Getting specific property values
• Setting custom properties on issues
• Deleting issue properties

This is useful for storing custom metadata on issues.
Implementation should be in IssueDomainExtensions.cs.</issue_description>

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

• Fixes Add support for JIRA Issue Properties API #94

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✅ Lakritzator
❌ Copilot
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[Lakritzator]

@copilot solve the merge conflict in IssueDomainExtensions

[Copilot]

@copilot solve the merge conflict in IssueDomainExtensions

Resolved the merge conflict in IssueDomainExtensions.cs. The file now includes both the voting/watcher methods from master and the issue property methods from this PR. Commit: 2b9a8c9