release: finalize and publish DnsSwitcher v1.5.0

[Regstar2]

Summary

Finalizes stable v1.5.0 after completed Windows validation.

Included

• final RU/EN README with stable status and real screenshots;
• final RU/EN release notes and GitHub Release body;
• CHANGELOG closed for 1.5.0 on 2026-08-19;
• manual/final-smoke evidence marked passed based on owner-confirmed validation;
• docs/versions/v1.5.0.md and synchronized release/version indexes;
• private AGENTS.md and .project-rules/* removed from Git tracking while remaining ignored by .gitignore;
• post-PR Tray/localization fixes and tests already present on release/v1.5.0 retained;
• one-shot publish-v1.5.0.yml workflow.

Publication behavior

After squash merge to main, the one-shot workflow:

1. checks out the exact merge commit;
2. runs restore/build/test;
3. builds the self-contained installer and portable ZIP;
4. verifies SHA256SUMS.txt against both final binaries;
5. creates v1.5.0 as a draft release, uploads all three assets, then makes it stable only if all uploads succeed;
6. deletes obsolete non-main branches after successful publication.

The workflow refuses to replace an existing v1.5.0 release.

Validation

The owner confirmed all planned Windows tests pass. The publish workflow repeats automated build/tests and packaging on the exact final commit before release creation.

Known limitation

The repository is private, so anonymous in-app GitHub Releases discovery remains unavailable. No embedded GitHub credential workaround is introduced.