fix(tests, monitoring): fix test scanId extraction and PromQL dashboard bug

The PromQL expression (time() * 1000 - scan_start_time) / 1000 was evaluating
to time() when scan_start_time = 0, causing massive spikes. The fix ensures
the expression only evaluates when scan_start_time > 0, filtering out idle
processors.
Issue: BB-740

Author: benzekrimaha

monitoring/lifecycle/dashboard.json

@@ -4647,7 +4647,7 @@
       "targets": [
         {
           "datasource": null,
-          "expr": "(time() * 1000 - s3_lifecycle_bucket_processor_scan_start_time{job=\"${job_lifecycle_bucket_processor}\", namespace=\"${namespace}\"}) / 1000 > 0",
+          "expr": "(time() * 1000 - s3_lifecycle_bucket_processor_scan_start_time{job=\"${job_lifecycle_bucket_processor}\", namespace=\"${namespace}\"}) / 1000 and s3_lifecycle_bucket_processor_scan_start_time{job=\"${job_lifecycle_bucket_processor}\", namespace=\"${namespace}\"} > 0",
           "format": "time_series",
           "hide": false,
           "instant": false,

monitoring/lifecycle/dashboard.py

@@ -815,7 +815,9 @@ def color_override(name, color):
         Target(
             expr='(time() * 1000 - '
                 + Metrics.BUCKET_PROCESSOR_SCAN_START_TIME()
-                + ') / 1000 > 0',
+                + ') / 1000 and '
+                + Metrics.BUCKET_PROCESSOR_SCAN_START_TIME()
+                + ' > 0',
             legendFormat='{{pod}}',
         ),
     ],

tests/unit/lifecycle/LifecycleConductor.spec.js

@@ -238,21 +238,35 @@ describe('Lifecycle Conductor', () => {
                 setData: (path, data, version, cb) => cb(null, { version: 1 }),
             };
             conductor._producer = { send: (msg, cb) => cb(null, {}) };
+            const addDefaultFieldsStub = sinon.stub();
+            const testLog = conductor.logger.newRequestLogger();
+            testLog.addDefaultFields = addDefaultFieldsStub;
+            sinon.stub(conductor.logger, 'newRequestLogger').returns(testLog);
 
             sinon.stub(conductor, '_controlBacklog').callsFake(cb => cb(null));
+            let capturedScanId = null;
             sinon.stub(conductor, 'listBuckets')
                 .callsFake((queue, scanId, log, cb) => {
                     // Verify scanId is a valid UUID
                     const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
                     assert(uuidRegex.test(scanId),
                         `conductorScanId should be a valid UUID v4, got: ${scanId}`);
+                    capturedScanId = scanId;
+                    assert(addDefaultFieldsStub.calledOnce);
+                    assert.strictEqual(addDefaultFieldsStub.firstCall.args[0].conductorScanId, scanId);
                     cb(null, 0);
                 });
             const metricStub = sinon.stub(LifecycleMetrics, 'onConductorFullScan');
 
             conductor.processBuckets(err => {
                 assert.ifError(err);
                 assert(metricStub.calledOnce);
+                const logPassedToMetric = metricStub.firstCall.args[0];
+                assert.strictEqual(logPassedToMetric, testLog);
+                assert(capturedScanId);
+                const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
+                assert(uuidRegex.test(capturedScanId),
+                    `captured conductorScanId should be a valid UUID v4, got: ${capturedScanId}`);
                 done();
             });
         });