ref(kafka): [Queue Instrumentation 20] Log Kafka instrumentation failures

Previously `SentryKafkaProducerInterceptor.onSend(...)` and
`SentryKafkaConsumerTracing` silently swallowed any `Throwable` thrown
while instrumenting a Kafka record. That protects customer Kafka I/O
from breakage, but makes instrumentation bugs invisible.

Log each caught `Throwable` to the SDK logger at `SentryLevel.ERROR`
(matching the existing pattern in `RequestPayloadExtractor`) before
continuing the fail-open path:

- `SentryKafkaProducerInterceptor`: producer span creation / header injection
- `SentryKafkaConsumerTracing`: scope fork + `makeCurrent`, transaction
  start, transaction finish

No behavior change for customer callbacks or Kafka send/receive: the
catches still swallow the throwable, they now just surface it via the
SDK's own logger.

`SentryKafkaRecordInterceptor` (Spring) was reviewed and intentionally
left as-is — it does not wrap its instrumentation in `catch (Throwable)`
blocks, so there is nothing silent to log. The `NumberFormatException`
branches on malformed `sentry-task-enqueued-time` headers are expected
input, not instrumentation faults, and remain silent.

Author: adinauer

sentry-kafka/src/main/java/io/sentry/kafka/SentryKafkaConsumerTracing.java

@@ -6,6 +6,7 @@
 import io.sentry.ISentryLifecycleToken;
 import io.sentry.ITransaction;
 import io.sentry.ScopesAdapter;
+import io.sentry.SentryLevel;
 import io.sentry.SentryTraceHeader;
 import io.sentry.SpanDataConvention;
 import io.sentry.SpanStatus;
@@ -83,7 +84,11 @@ <K, V, U> U withTracingImpl(
     try {
       forkedScopes = scopes.forkedRootScopes(CREATOR);
       lifecycleToken = forkedScopes.makeCurrent();
-    } catch (Throwable ignored) {
+    } catch (Throwable t) {
+      scopes
+          .getOptions()
+          .getLogger()
+          .log(SentryLevel.ERROR, "Failed to fork scopes for Kafka consumer tracing.", t);
       return callable.call();
     }
 
@@ -175,7 +180,11 @@ private boolean isIgnored() {
       }
 
       return transaction;
-    } catch (Throwable ignored) {
+    } catch (Throwable t) {
+      scopes
+          .getOptions()
+          .getLogger()
+          .log(SentryLevel.ERROR, "Failed to start Kafka consumer tracing transaction.", t);
       return null;
     }
   }
@@ -194,8 +203,12 @@ private void finishTransaction(
         transaction.setThrowable(throwable);
       }
       transaction.finish();
-    } catch (Throwable ignored) {
+    } catch (Throwable t) {
       // Instrumentation must never break customer processing.
+      scopes
+          .getOptions()
+          .getLogger()
+          .log(SentryLevel.ERROR, "Failed to finish Kafka consumer tracing transaction.", t);
     }
   }
 

sentry-kafka/src/main/java/io/sentry/kafka/SentryKafkaProducerInterceptor.java

@@ -5,6 +5,7 @@
 import io.sentry.IScopes;
 import io.sentry.ISpan;
 import io.sentry.ScopesAdapter;
+import io.sentry.SentryLevel;
 import io.sentry.SentryTraceHeader;
 import io.sentry.SpanDataConvention;
 import io.sentry.SpanOptions;
@@ -71,8 +72,11 @@ public SentryKafkaProducerInterceptor(
 
       span.setStatus(SpanStatus.OK);
       span.finish();
-    } catch (Throwable ignored) {
-      // Instrumentation must never break the customer's Kafka send.
+    } catch (Throwable t) {
+      scopes
+          .getOptions()
+          .getLogger()
+          .log(SentryLevel.ERROR, "Failed to instrument Kafka producer record.", t);
     }
 
     return record;