feat: add Team billing tier

Widens the tier enum from free/pro to free/pro/team and every
"free" | "pro" cast that assumed exactly two tiers (~30 call sites:
every AI route's withAiQuota/checkAndIncrementTierLimit call, admin
user/invite management, upload quota checks, OpenAPI schemas). Team
sits above Pro with genuinely unlimited recipes/public-recipes (the
-1 sentinel, which Pro doesn't actually use — Pro uses large finite
numbers instead) and a higher AI-call/storage cap. Seeded via
db:seed, editable afterward from Admin > Tiers.

role (user/moderator/admin — permissions) and tier (free/pro/team —
billing limits) stay separate concepts, as they already were; this
does not touch role-based permissions.

Requires migration 0043 to run against a live DB — not applied in
this sandbox (no Docker here); run `pnpm db:migrate` then `pnpm db:seed`.

v0.44.0

packages/db/src/seed.ts

@@ -20,6 +20,15 @@ async function seed() {
         storageMb: 10000,
         maxPublicRecipes: 99999,
       },
+      {
+        tier: "team",
+        // -1 is the actual "no cap" sentinel (see lib/tiers.ts UNLIMITED) —
+        // pro uses large-but-finite numbers instead; team is genuinely unlimited.
+        maxRecipes: -1,
+        aiCallsPerMonth: 2000,
+        storageMb: 50000,
+        maxPublicRecipes: -1,
+      },
     ])
     .onConflictDoNothing();