Merge branch 'pratik/otel-phase6-statsd' into pratik/otel-phase7-native-metrics

# Conflicts:
#	OpenTelemetryPlan/09-data-collection-reference.md

src/xrpld/app/ledger/detail/BuildLedger.cpp

@@ -50,7 +50,9 @@ buildLedgerImpl(
     ApplyTxs&& applyTxs)
 {
     using namespace telemetry;
-    auto buildSpan = SpanGuard::span(TraceCategory::Ledger, seg::ledger, ledger_span::op::build);
+    // Scoped so tx.apply (created synchronously below during applyTxs on this
+    // thread) nests under it. buildLedgerImpl runs synchronously with no yield.
+    auto buildSpan = ScopedSpanGuard(TraceCategory::Ledger, seg::ledger, ledger_span::op::build);
 
     auto built = std::make_shared<Ledger>(*parent, closeTime);
 

src/xrpld/rpc/detail/PathRequest.cpp

@@ -739,7 +739,9 @@ PathRequest::doUpdate(
 {
     using namespace std::chrono;
     using namespace telemetry;
-    auto span = SpanGuard::span(
+    // Scoped so pathfind.discover (created synchronously below via findPaths)
+    // nests under it. doUpdate does not yield, so scoping is safe.
+    auto span = ScopedSpanGuard(
         TraceCategory::Rpc, pathfind_span::prefix::pathfind, pathfind_span::op::compute);
     span.setAttribute(pathfind_span::attr::fast, fast);
     span.setAttribute(pathfind_span::attr::destCurrency, to_string(saDstAmount_.asset()).c_str());

src/xrpld/rpc/handlers/orderbook/PathFind.cpp

@@ -19,7 +19,9 @@ json::Value
 doPathFind(RPC::JsonContext& context)
 {
     using namespace telemetry;
-    auto span = SpanGuard::span(
+    // Scoped so pathfind.compute/discover (created synchronously below on this
+    // thread) nest under it. doPathFind does not yield, so scoping is safe.
+    auto span = ScopedSpanGuard(
         TraceCategory::Rpc, pathfind_span::prefix::pathfind, pathfind_span::op::request);
     // Addresses are hashed before emission for privacy.
     if (auto const& src = context.params[jss::source_account]; src.isString())