fix: add ksr and tid handling to OpenTracing31Test inject extract

Update the test inject extract expectations to include _dd.p.ksr=1 in
x-datadog-tags and t.ksr:1 in tracestate for the UNSET sampling case,
following PTagsCodec ordering: dm -> tid -> ksr.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: bm1549

dd-java-agent/instrumentation/opentracing/opentracing-0.31/src/test/groovy/OpenTracing31Test.groovy

@@ -284,22 +284,30 @@ class OpenTracing31Test extends InstrumentationSpecification {
       "-${DDSpanId.toHexStringPadded(context.delegate.spanId)}" +
       "-" + (propagatedPriority > 0 ? "01" : "00")
     def expectedTracestate = "dd=s:${propagatedPriority};p:${DDSpanId.toHexStringPadded(context.delegate.spanId)}"
-    def expectedDatadogTags = null
+    def datadogTags = []
     if (propagatedPriority > 0) {
       def effectiveSamplingMechanism = contextPriority == UNSET ? AGENT_RATE : samplingMechanism
-      expectedDatadogTags = "_dd.p.dm=-" + effectiveSamplingMechanism
-      expectedTracestate+= ";t.dm:-" + effectiveSamplingMechanism
+      datadogTags << "_dd.p.dm=-" + effectiveSamplingMechanism
+      expectedTracestate += ";t.dm:-" + effectiveSamplingMechanism
+    }
+    def traceId = context.delegate.traceId as DDTraceId
+    if (traceId.toHighOrderLong() != 0) {
+      expectedTracestate += ";t.tid:${traceId.toHexStringPadded(32).substring(0, 16)}"
+      datadogTags << "_dd.p.tid=" + traceId.toHexStringPadded(32).substring(0, 16)
+    }
+    if (contextPriority == UNSET) {
+      expectedTracestate += ";t.ksr:1"
+      datadogTags << "_dd.p.ksr=1"
     }
-
     def expectedTextMap = [
       "x-datadog-trace-id"         : "$context.delegate.traceId",
       "x-datadog-parent-id"        : "$context.delegate.spanId",
       "x-datadog-sampling-priority": propagatedPriority.toString(),
       "traceparent"                : expectedTraceparent,
       "tracestate"                 : expectedTracestate,
     ]
-    if (expectedDatadogTags != null) {
-      expectedTextMap.put("x-datadog-tags", expectedDatadogTags)
+    if (!datadogTags.empty) {
+      expectedTextMap.put("x-datadog-tags", datadogTags.join(','))
     }
     textMap == expectedTextMap