[Backlog] Add GitHub Actions release automation for ConfluencePS tags

[lipkau]

Problem

ConfluencePS release flow is outdated and coupled to legacy build script behavior instead of a modern artifact-based tag release workflow.

Proposal

Implement a release.yml workflow similar to JiraPS that consumes the CI artifact for the tagged commit, publishes to PowerShell Gallery, and creates a GitHub Release.

Acceptance criteria

• Tag push v* triggers a release workflow.
• Workflow downloads the matching build artifact from CI and fails if missing.
• Workflow publishes ConfluencePS to PSGallery using repository secrets.
• Workflow creates/updates a GitHub Release with the packaged artifact.