fix(telemetry): resolve phase-7 clang-tidy findings

- OTelCollector::formatName made static (no member state); braces added;
  <cctype> added for std::tolower.
- Telemetry.cpp getMeter(): braces around single-statement if.
- GetMeter.cpp: drop unused <opentelemetry/metrics/meter.h> and
  sync_instruments.h; add <xrpl/beast/utility/Journal.h> and <memory>;
  make sdkProvider const.
- ValidationTracker.h: add <cstddef> for std::size_t.
- detail/ValidationTracker.cpp: use std::views::reverse range-based loop;
  add <ranges>.
- test ValidationTracker.cpp: use auto for cast result.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/libxrpl/beast/insight/OTelCollector.cpp

@@ -56,6 +56,7 @@
 
 #include <algorithm>
 #include <atomic>
+#include <cctype>
 #include <chrono>
 #include <cstdint>
 #include <memory>
@@ -490,8 +491,8 @@ public:
      * @param name  Raw metric name from beast::insight callers.
      * @return Fully-qualified metric name.
      */
-    std::string
-    formatName(std::string const& name) const;
+    static std::string
+    formatName(std::string const& name);
 
 private:
     /** Journal for log output. */
@@ -821,7 +822,7 @@ OTelCollectorImp::otelMeter() const
 }
 
 std::string
-OTelCollectorImp::formatName(std::string const& name) const
+OTelCollectorImp::formatName(std::string const& name)
 {
     // Produce a clean, lowercase, Prometheus-compatible metric name.
     // No prefix — the OTel resource (service.name) identifies the service.
@@ -831,9 +832,13 @@ OTelCollectorImp::formatName(std::string const& name) const
     for (char const c : name)
     {
         if (c == '.' || c == ' ')
+        {
             result += '_';
+        }
         else
+        {
             result += static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
+        }
     }
     return result;
 }

src/libxrpl/telemetry/Telemetry.cpp

@@ -535,8 +535,10 @@ public:
     getMeter(std::string_view name = kMeterName) override
     {
         if (!meterProvider_)
+        {
             return metrics_api::Provider::GetMeterProvider()->GetMeter(
                 std::string(name), std::string(kMeterVersion));
+        }
         return meterProvider_->GetMeter(std::string(name), std::string(kMeterVersion));
     }
 

src/tests/libxrpl/telemetry/GetMeter.cpp

@@ -17,18 +17,18 @@
 
 #ifdef XRPL_ENABLE_TELEMETRY
 
+#include <xrpl/beast/utility/Journal.h>
 #include <xrpl/telemetry/Telemetry.h>
 
 #include <gtest/gtest.h>
-#include <opentelemetry/metrics/meter.h>
 #include <opentelemetry/metrics/meter_provider.h>
 #include <opentelemetry/metrics/provider.h>
-#include <opentelemetry/metrics/sync_instruments.h>
 #include <opentelemetry/nostd/shared_ptr.h>
 #include <opentelemetry/sdk/metrics/meter_provider.h>
 #include <opentelemetry/sdk/metrics/meter_provider_factory.h>
 
 #include <cstdint>
+#include <memory>
 #include <string>
 
 using namespace xrpl;
@@ -85,7 +85,7 @@ TEST(GetMeter, global_provider_meter_accepts_updown_counter)
     // A views-less SDK MeterProvider with no reader is sufficient to prove the
     // API contract: it hands out a real (non-noop) Meter that creates working
     // instruments. No exporter/reader means no background threads or network.
-    std::shared_ptr<metrics_sdk::MeterProvider> sdkProvider =
+    std::shared_ptr<metrics_sdk::MeterProvider> const sdkProvider =
         metrics_sdk::MeterProviderFactory::Create();
     metrics_api::Provider::SetMeterProvider(
         opentelemetry::nostd::shared_ptr<metrics_api::MeterProvider>(sdkProvider));

src/tests/libxrpl/telemetry/ValidationTracker.cpp

@@ -176,7 +176,7 @@ TEST_F(ValidationTrackerTest, MaxPendingEventsTrimming)
     for (std::size_t i = 0; i < kCount; ++i)
     {
         auto const hash = makeHash(i + 1);
-        LedgerIndex const seq = static_cast<LedgerIndex>(i + 1);
+        auto const seq = static_cast<LedgerIndex>(i + 1);
         tracker_.recordOurValidation(hash, seq);
         tracker_.recordNetworkValidation(hash, seq);
     }

src/xrpld/telemetry/ValidationTracker.h

@@ -10,6 +10,7 @@
 
 #include <atomic>
 #include <chrono>
+#include <cstddef>
 #include <cstdint>
 #include <deque>
 #include <mutex>

src/xrpld/telemetry/detail/ValidationTracker.cpp

@@ -12,6 +12,7 @@
 #include <cstdint>
 #include <deque>
 #include <mutex>
+#include <ranges>
 
 namespace xrpl::telemetry {
 
@@ -255,11 +256,11 @@ void
 ValidationTracker::repairWindowEntry(std::deque<WindowEvent>& window, uint256 const& hash)
 {
     // Scan backwards since late repairs target recently added entries.
-    for (auto it = window.rbegin(); it != window.rend(); ++it)
+    for (auto& event : std::views::reverse(window))
     {
-        if (!it->agreed && it->ledgerHash == hash)
+        if (!event.agreed && event.ledgerHash == hash)
         {
-            it->agreed = true;
+            event.agreed = true;
             return;
         }
     }