fix(upgrade): compare prerelease versions per SemVer

[riglar]

Problem

dcd upgrade would not upgrade from 5.0.0-beta.0 to 5.0.0-beta.1, reporting "Already on the latest version" instead.

VersionService.isOutdated stripped the prerelease suffix before comparing:

const nums = version.split('-')[0].split('.').map(Number);

So 5.0.0-beta.0 and 5.0.0-beta.1 both collapsed to [5,0,0], compared equal, and the upgrade was treated as a no-op. The same outdated-version nudge in cloud.ts was affected.

Fix

Replace the naive major.minor.patch compare with a SemVer 2.0.0 compareSemver helper that handles prerelease precedence:

• A prerelease ranks below its final release (5.0.0-beta.1 < 5.0.0).
• Prerelease identifiers compare dot-by-dot: numeric numerically, alphanumeric lexically, numeric sorts below alphanumeric, more identifiers wins. So beta.0 < beta.1 and beta.2 < beta.10.

Added test/unit/version.service.test.ts covering the regression plus release/prerelease/equality/v-prefix cases. pnpm typecheck passes; all new tests pass.

Note

This fixes the comparator so future upgrades work. A binary already running the old beta.0 comparator still can't detect the bump — those users need one reinstall to pick up this fix, after which beta-to-beta upgrades work.

🤖 Generated with Claude Code

[claude]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.