fix(sentry): Log unknown key recovery failures

Log a second error when unknown-field recovery itself fails.
This makes nextUnknown consistent with the list and map recovery
paths and makes truncated payload failures easier to diagnose.

Add regression coverage for unknown-key deserialization failures
that also leave the stream unrecoverable.

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

Author: adinauer

sentry/src/main/java/io/sentry/JsonObjectReader.java

@@ -98,8 +98,11 @@ public void nextUnknown(ILogger logger, Map<String, Object> unknown, String name
       if (recoveryState != null) {
         try {
           recoverValue(recoveryState);
-        } catch (Exception ignored) {
-          // stream is unrecoverable
+        } catch (Exception recoveryException) {
+          logger.log(
+              SentryLevel.ERROR,
+              "Stream unrecoverable after unknown key deserialization failure.",
+              recoveryException);
         }
       }
     } finally {

sentry/src/test/java/io/sentry/JsonObjectReaderTest.kt

@@ -10,6 +10,7 @@ import org.mockito.kotlin.eq
 import org.mockito.kotlin.mock
 import org.mockito.kotlin.never
 import org.mockito.kotlin.verify
+import org.mockito.kotlin.verifyNoMoreInteractions
 
 class JsonObjectReaderTest {
   class Fixture {
@@ -424,6 +425,32 @@ class JsonObjectReaderTest {
       )
   }
 
+  @Test(timeout = 1000L)
+  fun `nextUnknown logs when recovery fails`() {
+    val unknown = mutableMapOf<String, Any>()
+    val reader = fixture.getSut("{\"key\": {\"value\": \"fail\"")
+    reader.beginObject()
+    val name = reader.nextName()
+
+    reader.nextUnknown(fixture.logger, unknown, name)
+
+    assertEquals(emptyMap(), unknown)
+    verify(fixture.logger)
+      .log(
+        eq(SentryLevel.ERROR),
+        any<Throwable>(),
+        eq("Error deserializing unknown key: %s"),
+        eq("key"),
+      )
+    verify(fixture.logger)
+      .log(
+        eq(SentryLevel.ERROR),
+        eq("Stream unrecoverable after unknown key deserialization failure."),
+        any<Throwable>(),
+      )
+    verifyNoMoreInteractions(fixture.logger)
+  }
+
   // nextDateOrNull
 
   @Test