fix(web-probe): aggregate numeric sse flush replacements

scripts/src/hwlab-node/web-observe-web-performance-payload.test.ts

@@ -119,12 +119,13 @@ async function writeState(): Promise<string> {
           traceId: "trc_webperf_fixture",
           sessionIdHash: "sha256:session",
           eventCount: 12,
+          deliveredCount: 10,
           chunkCount: 3,
           flushDurationMs: 18.75,
           droppedCount: 2,
           maxItemsPerChunk: 5,
           maxChunkMs: 7.5,
-          replacedByKey: true,
+          replacedByKey: 3,
           valuesRedacted: true,
         }],
         valuesRedacted: true,
@@ -181,9 +182,10 @@ test("analyzer and performance-summary include bounded web-performance runtime d
   assert.equal(groups[0].reason, "sse_flush");
   assert.equal(groups[0].module, "workbench-runtime");
   assert.equal(groups[0].eventCount, 12);
+  assert.equal(groups[0].deliveredCount, 10);
   assert.equal(groups[0].chunkCount, 3);
   assert.equal(groups[0].maxFlushDurationMs, 18.75);
-  assert.equal(groups[0].replacedByKeyCount, 1);
+  assert.equal(groups[0].replacedByKeyCount, 3);
 
   const reportText = JSON.stringify(report);
   assert.match(reportText, /workbench_sse_flush/u);
@@ -209,6 +211,6 @@ test("analyzer and performance-summary include bounded web-performance runtime d
   assert.match(renderedText, /Web performance runtime diagnostics/u);
   assert.match(renderedText, /payloads=3 parsed=1 parseIssues=2 events=1 groups=1/u);
   assert.match(renderedText, /workbench_sse_flush reason=sse_flush module=workbench-runtime/u);
-  assert.match(renderedText, /eventCount=12 chunks=3 flushMax=18.75ms dropped=2/u);
+  assert.match(renderedText, /eventCount=12 delivered=10 chunks=3 flushMax=18.75ms dropped=2/u);
   assert.match(renderedText, /payload states=invalid-json:1, not-parsed-over-limit:1, parsed:1/u);
 }, 20_000);