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

apps/web/app/api/v1/admin/users/[id]/route.ts

@@ -16,7 +16,7 @@ export async function PATCH(req: NextRequest, { params }: RouteContext) {
   const { role, tier } = body;
 
   const validRoles = ["user", "moderator", "admin"] as const;
-  const validTiers = ["free", "pro"] as const;
+  const validTiers = ["free", "pro", "team"] as const;
 
   if (role !== undefined && !validRoles.includes(role as typeof validRoles[number])) {
     return NextResponse.json({ error: "Invalid role" }, { status: 400 });
@@ -25,11 +25,11 @@ export async function PATCH(req: NextRequest, { params }: RouteContext) {
     return NextResponse.json({ error: "Invalid tier" }, { status: 400 });
   }
 
-  const updateData: Partial<{ role: "user" | "moderator" | "admin"; tier: "free" | "pro"; updatedAt: Date }> = {
+  const updateData: Partial<{ role: "user" | "moderator" | "admin"; tier: "free" | "pro" | "team"; updatedAt: Date }> = {
     updatedAt: new Date(),
   };
   if (role) updateData.role = role as "user" | "moderator" | "admin";
-  if (tier) updateData.tier = tier as "free" | "pro";
+  if (tier) updateData.tier = tier as "free" | "pro" | "team";
 
   const [updated] = await db
     .update(users)