We’re building a patient-facing health dashboard where users can log daily vitals (e.g., systolic blood pressure, blood glucose) and later view chart-ready histories for a single metric over a selected date range. Please design a small REST API that supports this workflow:

- POST /v1/me/vitals: patients submit a reading with { type, value, unit, measuredAt }.
- GET /v1/me/vitals?type=...&from=...&to=...: returns the time series for that vital for the chosen window.

Authentication is via the patient’s JWT (Bearer). The service should strongly validate inputs to prevent unrealistic values or mismatched units and enforce well-formed timestamps. Use PostgreSQL and model the data for fast time-range queries as records grow; a composite index on (patient_id, type, measured_at) is expected. Focus on the API contract, validation rules, and schema that reliably feed charting in the dashboard; Go (Gin or similar) can be used for the implementation.