fix: update sessionBucket to use 'boat' and refine session query logic

api/src/routes/sessions.js

@@ -11,7 +11,6 @@ router.get('/history', async (req, res) => {
     try {
         const sessions = await listInfluxSessions();
 
-        // Arricchisci con dati PostgreSQL (opzionale — può fallire senza bloccare)
         let pgMap = {};
         try {
             const result = await dbQuery(

api/src/storage/influx.js

@@ -60,7 +60,7 @@ async function query(bucket, relativeTime, measurement, sensor, field) {
 
 }
 
-const sessionBucket = process.env.INFLX_BUCKET || 'logs';
+const sessionBucket = 'boat';
 
 /**
  * Query storica per una sessione di registrazione.
@@ -144,11 +144,10 @@ async function listInfluxSessions(lookback = '-5y') {
             |> range(start: ${lookback})
             |> filter(fn: (r) => r._measurement == "logs")
             |> group(columns: ["sensor", "session"])
-            |> keep(columns: ["_time", "sensor", "session"])
     `;
     const [firstRows, lastRows] = await Promise.all([
-        runFlux(base + '|> first()'),
-        runFlux(base + '|> last()'),
+        runFlux(base + '|> first() |> keep(columns: ["_time", "sensor", "session"])'),
+        runFlux(base + '|> last()  |> keep(columns: ["_time", "sensor", "session"])'),
     ]);
 
     const map = {};