Tracking pixel and click URLs point to /api/track but the API serves /track #30

Tracking URLs in outgoing mail point at /api/track/..., but the Express app serves the tracking router at /track/.... The web app has no /api/track route either.

• apps/api/src/automation/process-ongoing-sequence.ts:268,291
• apps/api/src/mail/worker.ts:131,141
• Router mount: app.use(trackingRoutes) in apps/api/src/index.ts
• Unsubscribe links use ${getSiteUrl()}/unsubscribe/... with no /api prefix, so the two disagree about what DOMAIN points to.

With the Compose default DOMAIN=localhost:4000 (the API), unsubscribe links work but open pixels and click redirects return 404. Every click in a campaign is then a broken link. This only works if a production reverse proxy strips /api.

Fix

• Pick one base for public API links (for example a PUBLIC_API_URL / getSiteUrl() that always targets the API) and drop the /api prefix, or mount the tracking router under /api as well.
• Update process-ongoing-sequence.test.ts:276-277, which currently asserts the broken path.
• Add a test that resolves a generated tracking URL against the Express app.