Issue #549 — backend validation verification (staging)
========================================================

Backend: http://localhost:3549 (fix/549 worktree)
DB:      staging TiDB (gateway01.us-east-1.prod.aws.tidbcloud.com:4000/nexuscrm)

---- 1. Empty POST rejected with REQUIRED_FIELD_MISSING ----

Request:
  POST /services/data/v63.0/sobjects/Lead
  body: {}

Response (HTTP 400):
  [
    {
      "errorCode": "REQUIRED_FIELD_MISSING",
      "message": "validation error on field 'Company,LastName,Name,Status':
                  required field(s) missing: Company, LastName, Name, Status"
    }
  ]

---- 2. Full payload accepted (HTTP 201) ----

Request:
  POST /services/data/v63.0/sobjects/Lead
  body: {
    "Name":    "Smith-Test549-B",
    "LastName":"SmithB",
    "Company": "Acme Corp Test B",
    "Status":  "Engaged"
  }

Response (HTTP 201):
  {"errors":[],"id":"ed131b7d-7f7a-4989-9ac2-0725965ea772","success":true}

DB verification (SELECT from `lead`):
  Id                                   | Name            | LastName | Company          | Status
  -------------------------------------+-----------------+----------+------------------+-------
  ed131b7d-7f7a-4989-9ac2-0725965ea772 | Smith-Test549-B | SmithB   | Acme Corp Test B | Engaged

---- 3. Frontend client-side validation ----

/object/lead/new with empty save triggered react-hook-form validation:
  - "3 fields require attention."
  - 3 x "This field is required" inline errors under Name, Company, Status
  - No POST request was sent to the backend (validation gate before submit)
  - Form did not navigate (URL stayed /object/lead/new)

Screenshots:
  549-04-required-markers.png  — form shows Name*, Company*, Status* markers
  549-05-empty-save-blocked.png — error summary + inline errors after Save click

---- 4. Before-fix state (for contrast) ----

DB before:
  _System_Field.Required = 0 for Lead.Name/LastName/Company/Status
Backend describe response:
  nillable: true for all four (derived from Required=0)
Frontend form:
  No `*` markers anywhere, per issue #549 reproduction on live staging.
Backend POST /sobjects/Lead with {} :
  201 Created with NULL name/company/status (junk record polluting table).