Chat: request telemetry in its own table, 30-day retention (#99)

ddiff --git a/migrations/0011_telemetry.sql b/migrations/0011_telemetry.sql
nnew file mode 100644
iindex 0000000..14260fa
---- /dev/null
++++ b/migrations/0011_telemetry.sql
@@@ -0,0 +1,28 @@
++-- phase: expand
++-- Request telemetry (openvibe-sdk/telemetry telemetrySchema()): one row per aggregated sample, pruned after 30 days (server/index.js).
++CREATE TABLE IF NOT EXISTS telemetry_samples (
++    id                    bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
++    at                    timestamptz NOT NULL,
++    service               text NOT NULL,
++    project               text,
++    subject               text,
++    resource              text,
++    provider              text,
++    node                  text,
++    cell                  text,
++    region                text,
++    operation             text NOT NULL,
++    latency_ms            double precision,
++    queue_delay_ms        double precision,
++    ttfb_ms               double precision,
++    throughput_per_second double precision,
++    bytes                 bigint,
++    status                text,
++    cache_status          text,
++    cost_estimate         double precision,
++    route_epoch           bigint,
++    trace_id              text,
++    extra                 jsonb NOT NULL DEFAULT '{}'::jsonb
++);
++CREATE INDEX IF NOT EXISTS telemetry_samples_at_idx ON telemetry_samples (at);
++CREATE INDEX IF NOT EXISTS telemetry_samples_service_idx ON telemetry_samples (service, operation, at);
ddiff --git a/server/app.js b/server/app.js
iindex 108f9a4..fcff1ed 100644
---- a/server/app.js
++++ b/server/app.js
@@@ -77,6 +77,7 @@ function createApp({ chatServer, relay, events = null, callServer = null }) {
      // request rates/latencies and process metrics, from openvibe-shared (before any route).
      const release = require('openvibe-shared/release').createRelease({ service: 'chat', root: require('path').join(__dirname, '..'), packages: ['openvibe-shared', 'openvibe-sdk', 'openvibe-contracts'] });
      const metrics = require('openvibe-shared/metrics').instrument(app, { service: 'chat', release: release.release });
++    app.use(require('openvibe-sdk/service').telemetryMiddleware);   // request telemetry: a no-op until server/index.js calls telemetry.init()
      release.mount(app, { registry: metrics.registry });
      app.locals.metrics = metrics.registry;
      // How sign-ins resolve (auth/network-session.js): here, through Live, or refused.
ddiff --git a/server/index.js b/server/index.js
iindex 762dbf9..b4f737c 100644
---- a/server/index.js
++++ b/server/index.js
@@@ -23,7 +23,8 @@ const subscriptions = require('./events/subscriptions');
  const chatAi = require('./ai/chat-ai');
  const { limits } = require('./net/actor-limits');
  const { createValkey } = require('openvibe-sdk/valkey');
--const { gracefulStop } = require('openvibe-sdk/service');
++const { gracefulStop, telemetry } = require('openvibe-sdk/service');
++const { createPgTelemetrySink, startTelemetryRetention } = require('openvibe-sdk/telemetry');
  const { createApp } = require('./app');
  
  let rejectionsLogged = false;
@@@ -67,6 +68,10 @@ async function start() {
      await new Promise((resolve) => server.listen(config.port, config.host, resolve));
      console.log(`[Chat] listening on http://${config.host}:${server.address().port} (ws /ws/chat${config.calls.enabled ? ', /ws/call' : ''})`);
      const subs = subscriptions.startAtBoot({ config, port: server.address().port });
++    // Request telemetry (openvibe-sdk/service, plan T1): one aggregated sample per route template, method and status
++    // class each minute, stored in this service's telemetry_samples table; rows older than 14 days go daily.
++    telemetry.init({ service: 'chat', sink: createPgTelemetrySink({ db: db.getDb(), log: console }), skipPrefixes: ['/shared'], intervalMs: 60_000 });
++    const telemetryRetention = startTelemetryRetention({ db: db.getDb(), log: console, olderThanDays: 14 });
  
      // systemd sends SIGTERM (SIGINT by hand); openvibe-sdk/service's gracefulStop takes the signal, runs the stop
      // steps in order (nothing new starts), drains the HTTP server, runs the close steps, then exits 0. drainMs
@@@ -94,7 +99,7 @@ async function start() {
              () => chatServer.close(),
              () => callServer.close(),
          ],
--        close: [() => db.close()],
++        close: [async () => { if (telemetryRetention) await telemetryRetention.stop(); await telemetry.stop(); }, () => db.close()],
      });
      return { server, relay, events, callServer, subscriptions: subs, shutdown };
  }
ddiff --git a/test/pg-schema.test.js b/test/pg-schema.test.js
iindex 58ed27e..2889f47 100644
---- a/test/pg-schema.test.js
++++ b/test/pg-schema.test.js
@@@ -28,7 +28,7 @@ const TABLES = [
      'ctx_users', 'ctx_streams', 'ctx_managed_streams', 'ctx_channels', 'ctx_sync', 'events_outbox', 'service_outbox',
      'chat_ingress_applied', 'audio_requests', 'import_hold', 'import_runs', 'chat_meta', 'deploy_releases',
      'chat_event_inbox', 'calls', 'rooms', 'room_members', 'room_messages', 'room_attachments', 'token_revocations', 'chat_control_log',
--    'network_blocks', 'account_data_events', 'ticket_conversations', 'ticket_messages',
++    'network_blocks', 'account_data_events', 'ticket_conversations', 'ticket_messages', 'telemetry_samples',
  ];
  const INDEXES = [
      'idx_chat_ts_deleted', 'idx_chat_page_live', 'idx_chat_channel_user_ts', 'idx_chat_stream_ts', 'idx_emotes_channel_code', 'idx_chat_tl_dedup',
ddiff --git a/test/telemetry.test.js b/test/telemetry.test.js
nnew file mode 100644
iindex 0000000..3d08a92
---- /dev/null
++++ b/test/telemetry.test.js
@@@ -0,0 +1,50 @@
++'use strict';
++/**
++ * Request telemetry (openvibe-sdk/service, plan T1 step 10): app.js mounts the process-wide telemetryMiddleware (a no-op
++ * until init), server/index.js calls telemetry.init() for service 'chat' with a PostgreSQL sink, starts the 14-day
++ * retention and flushes on stop. Five hits on one route flush as ONE aggregated http.request sample; /metrics and
++ * /shared make none; the retention deletes only rows older than 14 days.
++ */
++const assert = require('assert');
++const fs = require('fs');
++const path = require('path');
++const { telemetry } = require('openvibe-sdk/service');
++const { pruneTelemetry } = require('openvibe-sdk/telemetry');
++const { boot } = require('./helpers');
++(async () => {
++    const read = (p) => fs.readFileSync(path.join(__dirname, '..', p), 'utf8');
++    assert.match(read('server/index.js'), /telemetry\.init\(\{ service: 'chat', sink: createPgTelemetrySink\(/, 'index.js starts the collector');
++    assert.match(read('server/index.js'), /startTelemetryRetention\(/, 'index.js starts the retention');
++    assert.match(read('server/index.js'), /[Rr]etention\.stop\(\); await telemetry\.stop\(\);/, 'the stop flushes');
++
++    const t = await boot();
++    const samples = [];
++    telemetry.init({ service: 'chat', sink: async (batch) => { samples.push(...batch); }, intervalMs: 3600e3 });
++    const requests = () => samples.filter((s) => s.operation === 'http.request');
++    try {
++        for (let i = 0; i < 5; i++) assert.strictEqual((await fetch(t.base + '/')).status, 200);
++        await telemetry.flush();
++        const hit = requests().filter((s) => s.resource === '/' && s.status === '2xx');
++        assert.strictEqual(hit.length, 1, JSON.stringify(requests()));
++        assert.strictEqual(hit[0].service, 'chat');
++        assert.strictEqual(hit[0].extra.count, 5);
++
++        samples.length = 0;
++        await await fetch(t.base + '/metrics');
++        await await fetch(t.base + '/shared/navbar.js');
++        await telemetry.flush();
++        assert.deepStrictEqual(requests(), [], '/metrics and /shared make no sample');
++
++        const db = require('../server/db/database').getDb();
++        await db.query('DELETE FROM telemetry_samples');
++        const insert = (days) => db.query("INSERT INTO telemetry_samples (at, service, operation) VALUES (now() - make_interval(days => $1), 'chat', 'http.request')", [days]);
++        await insert(20);
++        await insert(1);
++        assert.strictEqual(await pruneTelemetry({ db, olderThanDays: 14 }), 1);
++        assert.strictEqual((await db.query('SELECT count(*)::int AS n FROM telemetry_samples')).rows[0].n, 1);
++        process.stdout.write('telemetry ok\n');
++    } finally {
++        await telemetry.stop();
++        if (t && t.close) await t.close();
++    }
++})().then(() => process.exit(0), (err) => { process.stderr.write(`${(err && err.stack) || err}\n`); process.exit(1); });   // the helper keeps sockets open