release: prepare first public alpha

[utrost]

Summary

• Prepare v1.0.0-alpha.1 release notes and release-result checklist
• Make release scripts support a release label that differs from the Maven project version
• Mark hyphenated tags as GitHub pre-releases and use matching release notes when present
• Point README users at GitHub Releases as the external tester path
• Allow committed Markdown release-result records while keeping generated artifacts ignored

Verification

• bash -n scripts/build.sh
• bash -n scripts/release.sh
• XML project-version extraction returns 1.0.0
• Markdown relative-link check: OK
• GitHub workflow YAML parse: OK
• git diff --check: OK

Local limitation

• Local artifact build still cannot run on Alice because mvn is not installed; GitHub CI/release runners have Maven via setup-java/cache and will perform the real build.

Closes #14 after the v1.0.0-alpha.1 tag publishes successfully.