fix(settings): link release notes before updates

[fengjikui]

Summary

• add a shared helper for version-specific GitHub release URLs
• show a View release notes link next to the settings update Download button
• add a View Release Notes option to the auto-update confirmation dialog

Fixes #2006

Validation

• pnpm exec vitest run renderer/src/common/components/settings/tabs/tests/version-tab.test.tsx main/src/tests/auto-update.test.ts
• pnpm run prettier
• pnpm run lint
• pnpm run type-check
• git diff --check