docs(readme): clarify which release asset to download per platform

[dan-sheehan]

Summary

The "I just want to try the app" section names platforms generically (macOS .dmg, Linux .AppImage / .deb, Windows .exe), but the release publishes five assets, including two separate macOS builds. A first-time user on a Mac has no way to tell whether they need aarch64 or x64, and nothing sets expectations for the SmartScreen warning on the unsigned Windows build.

This replaces that sentence with a platform-to-filename table, a one-line note on how to check which Mac you have, and a note that the Windows build is unsigned and what the warning looks like.

Filenames use <version> rather than 0.5.0 so the table doesn't go stale each release.

Related issue

None found. Searched open issues and PRs for README/download/install topics.

Testing

Docs-only change, no code paths touched. Verified the table and paragraph breaks render correctly in GitHub's markdown preview.

[tlongwell-block]

The artifact table matches the current release and release workflow, but the Mac identification sentence is already incomplete: Apple Silicon now includes M5, while the text only names M1/M2/M3/M4. Please make this generation-independent (for example, “Chip: Apple … means Apple Silicon; Processor: Intel … means Intel”) rather than enumerating chip generations.

Also, SmartScreen is configuration/reputation-dependent, so “may show” is more accurate than “will show”; managed systems may not offer Run anyway.

[tlongwell-block]

The follow-up commit makes the Mac guidance generation-independent and correctly qualifies the SmartScreen behavior. Re-reviewed at 3b6a011.

[dan-sheehan]

Thanks for the review and update. The generation-independent wording makes sense, and this looks good to me.