Canvas will be served at <slug>.moleculesai.app (Vercel). API calls go
cross-origin to https://app.moleculesai.app. This commit wires the
client side:
- canvas/src/lib/tenant.ts: getTenantSlug() derives the slug from
window.location.hostname, case-insensitive, matching the control
plane's reservedSubdomains list (app/www/api/admin/…). Server-side
+ localhost + vercel preview URLs + apex all return "" so local dev
keeps working.
- canvas/src/lib/api.ts: adds X-Molecule-Org-Slug header + sets
credentials:"include" on every fetch. The control plane's CORS
middleware allows the origin + credentials; the session cookie has
Domain=.moleculesai.app so the browser ships it.
- canvas/src/lib/api/secrets.ts: same treatment (secrets API uses its
own fetch helper — shared slug+credentials logic applied).
Tests: +6 (tenant.test.ts covers slug / reserved / case / non-SaaS /
preview URL / apex). Full canvas suite 447/447 green.
Not in this PR:
- WS URL derivation for terminal/socket.ts (separate follow-up; WS
needs its own slug-aware URL and the canvas terminal isn't used in
SaaS launch day-one).
- Next.js rewrites (decided against; cross-origin with credentials
is cleaner than path-level rewrites for session cookies).
Deploys to Vercel once merged — no manual config needed (env already set).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
