fix telemtrie na dahsbaordu (15min misto 1h)

db/migration/V039__telemetry_inverter_15m_aggregate.sql

@@ -0,0 +1,33 @@
+-- ============================================================
+-- 15min continuous aggregate telemetrie střídače (dashboard sloty)
+-- ============================================================
+-- Zarovnáno s 15min sloty UI (UTC time_bucket = floorSlotUtcMs v frontendu).
+-- Hodinový CA telemetry_inverter_hourly zůstává pro dlouhé grafy / legacy.
+
+CREATE MATERIALIZED VIEW IF NOT EXISTS ems.telemetry_inverter_15m
+WITH (timescaledb.continuous) AS
+SELECT
+    time_bucket('15 minutes', measured_at) AS slot_start,
+    site_id,
+    AVG(pv_power_w)::INT                  AS avg_pv_w,
+    AVG(battery_power_w)::INT             AS avg_battery_w,
+    AVG(grid_power_w)::INT                AS avg_grid_w,
+    AVG(load_power_w)::INT                AS avg_load_w,
+    LAST(battery_soc_percent, measured_at) AS last_soc_pct,
+    COUNT(*)                               AS sample_count
+FROM ems.telemetry_inverter
+GROUP BY slot_start, site_id
+WITH NO DATA;
+
+-- Refresh: ≥2× time_bucket (15 min) → start_offset > 30 min
+SELECT add_continuous_aggregate_policy(
+    'ems.telemetry_inverter_15m',
+    start_offset       => INTERVAL '45 minutes',
+    end_offset         => INTERVAL '1 minute',
+    schedule_interval  => INTERVAL '15 minutes'
+);
+
+COMMENT ON MATERIALIZED VIEW ems.telemetry_inverter_15m IS
+'Čtvrthodinové agregáty telemetrie střídače. TimescaleDB continuous aggregate.
+Refresh každých 15 minut. Dashboard přehled (sloty 15 min).
+View vw_telemetry_15m_7d je v repeatable R__vw_telemetry_15m_7d.sql.';