fix(telemetry): address remaining clang-tidy and cspell CI failures

- Add "hicpp" to cspell dictionary for NOLINT annotations
- Concatenate nested namespaces in RpcSpanNames.h
- Fix include hygiene and nested ternary in RPCHandler.cpp

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

cspell.config.yaml

@@ -117,6 +117,7 @@ words:
   - gpgcheck
   - gpgkey
   - hotwallet
+  - hicpp
   - hwaddress
   - hwrap
   - ifndef

src/xrpld/rpc/detail/RPCHandler.cpp

@@ -17,15 +17,16 @@
 #include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 #include <xrpl/resource/Fees.h>
-#include <xrpl/server/InfoSub.h>
 #include <xrpl/server/NetworkOPs.h>
 #include <xrpl/telemetry/SpanGuard.h>
+#include <xrpl/telemetry/SpanNames.h>
 
 #include <atomic>
 #include <chrono>
 #include <cstdint>
 #include <exception>
 #include <string>
+#include <string_view>
 
 namespace xrpl {
 using namespace telemetry;
@@ -214,10 +215,11 @@ doCommand(RPC::JsonContext& context, Json::Value& result)
     Handler const* handler = nullptr;
     if (auto error = fillHandler(context, handler))
     {
-        std::string const cmdName = context.params.isMember(jss::command)
-            ? context.params[jss::command].asString()
-            : context.params.isMember(jss::method) ? context.params[jss::method].asString()
-                                                   : "unknown";
+        std::string cmdName = "unknown";
+        if (context.params.isMember(jss::command))
+            cmdName = context.params[jss::command].asString();
+        else if (context.params.isMember(jss::method))
+            cmdName = context.params[jss::method].asString();
         auto span = SpanGuard::span(
             TraceCategory::Rpc, rpc_span::prefix::command, rpc_span::val::unknownCommand);
         span.setAttribute(rpc_span::attr::command, cmdName.c_str());

src/xrpld/rpc/detail/RpcSpanNames.h

@@ -20,9 +20,7 @@
 
 #include <xrpl/telemetry/SpanNames.h>
 
-namespace xrpl {
-namespace telemetry {
-namespace rpc_span {
+namespace xrpl::telemetry::rpc_span {
 
 // ===== Span prefixes =======================================================
 
@@ -69,6 +67,4 @@ inline constexpr auto user = makeStr("user");
 inline constexpr auto unknownCommand = makeStr("unknown_command");
 }  // namespace val
 
-}  // namespace rpc_span
-}  // namespace telemetry
-}  // namespace xrpl
+}  // namespace xrpl::telemetry::rpc_span