Update an existing subscription for a tenant.

Supports changing the plan and/or the ending date. When changing the plan, the old subscription is terminated and a new one is created.

Use effective_date to schedule a future plan change instead of an immediate switch.

Access: mtk_admin and super_admin (scoped to hospital group)

Request body:

{
    "plan_code": "claim_mind_pro",
    "ending_at": "2027-01-31",
    "effective_date": null
}

{
  "plan_code": "claim_mind_pro"
}

{
  "subscription": {
    "created_at": "2026-01-22T10:00:00Z",
    "ending_at": "2027-01-31T23:59:59Z",
    "external_id": "tenant-001",
    "lago_id": "sub-lago-uuid-456",
    "plan_code": "claim_mind_basic",
    "plan_name": "ClaimMind Basic",
    "started_at": "2026-02-01T00:00:00Z",
    "status": "active"
  }
}