Walkthrough: create a segment with a wizard

GET /api/autoComplete?finder=byUserTraits&q=plan

→ { results: [{ name: "plan", type: "string", count: 5432 }] }

GET /api/autoComplete?finder=byUserTraits&q=last

→ { results: [{ name: "last_seen_at", type: "datetime", count: 5432 }] }

POST /api/dashboard/segmentsDefinition

{ "name": "Enterprise Users - Inactive 30 Days",
  "description": "Enterprise plan users who haven't logged in for 30+ days" }

→ { "id": "seg_9x8y7z6w", "definition": null }

POST /api/dashboard/segmentsDefinition?action=update&segmentId=seg_9x8y7z6w

{
  "definition": {
    "object": "All",
    "groups": [
      { "object": "Single", "type": "UserProperty",
        "traitName": "plan", "operation": { "type": "Equals", "operand": "enterprise" } },
      { "object": "Single", "type": "UserSeen",
        "userSeenRuleType": "LastSeen", "operation": { "type": "Outside", "operand": 30 } }
    ]
  }
}

→ { "id": "seg_9x8y7z6w", "memberCount": 247 }

GET /api/autoComplete?finder=byUserEmail&q=john@acme.com

→ { results: [{ userId: "usr_abc123", email: "john@acme.com" }] }

GET /api/dashboard/segmentMemberships/usr_abc123

→ { isMember: true, matchedRules: [
     { type: "UserProperty", traitName: "plan", matched: true },
     { type: "UserSeen", matched: true, daysSinceLastSeen: 45 }
   ] }