[Release] Publish canonical GitHub Releases and immutable version tags

[KeyffMS]

Parent project: #95
Depends on: #96, #82, #83, #84, #85, #91

Objective

Use GitHub Releases as the authoritative, dated publication history for SightAdapt versions and downloadable artifacts.

Acceptance criteria

• Define the release/tag naming convention, beginning with v0.5.0.50-alpha or the next approved version.
• Use release titles in the format SightAdapt™ <version>.
• Include the canonical product description in every release.
• Include release notes, supported Windows versions, known limitations and upgrade/migration notes.
• Attach the complete verified Windows archive, checksums, SBOM and legal bundle.
• Include links to https://sightadapt.aiteracja.pl/, documentation, privacy notice and source code.
• Make tags immutable after publication except for documented emergency withdrawal procedures.
• Document prerelease versus stable-release policy.
• Add a release checklist that verifies CI, manual tests, licenses and artifact hashes.
• Ensure the website can obtain the current version and download link from GitHub Releases without duplicating binary files.
• Publish a permanent release-history page linking every version and tag.

[KeyffMS]

Release-gate dependency update

PR #144 completed #82 and #91 and introduced the reusable maintained package entry point:

tools/new-verified-release-package.ps1

When implementing this Issue, the GitHub Release workflow must:

• change github-release from planned to maintained in release/distribution-channels.json;
• require an immutable tag matching refs/tags/<tag>;
• produce or consume the exact verified portable ZIP through the reusable entry point;
• publish the matching schema-3 compliance report alongside the ZIP;
• verify source commit/tag/workflow provenance and per-file staged/archive SHA-256 equality;
• avoid rebuilding or repackaging different bytes after verification.

The current final gate deliberately rejects github-release until these requirements are implemented.