Add docs for OpenTelemetry Java

src/platform-includes/performance/opentelemetry-install/with-java-agent/java.mdx

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+You can download the latest version of the `sentry-opentelemetry-agent-{{ packages.version('sentry.java.opentelemetry-agent') }}.zip` from [GitHub](https://github.com/getsentry/sentry-java/releases/) which contains the `JAR` file used in this docs page.

src/platform-includes/performance/opentelemetry-install/without-java-agent/java.mdx

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+In addition to OpenTelemetry dependencies and your typical Sentry dependencies, you will need to add `sentry-opentelemetry-core` as a dependency:
+
+```groovy {tabTitle:Gradle}
+implementation 'io.sentry:sentry-opentelemetry-core::{{ packages.version('sentry.java.opentelemetry-agent', '6.9.2') }}'
+```

src/platform-includes/performance/opentelemetry-setup/with-java-agent/exporter-messages/java.mdx

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+In case you are using `sentry-opentelemetry-agent` without needing to use any OpenTelemetry exporters you can add
+the following environment variables to turn off exporters and stop seeing error messages about
+servers not being reachable in the logs.
+
+Example log message:
+```
+ERROR io.opentelemetry.exporter.internal.grpc.OkHttpGrpcExporter - Failed to export spans. The request could not be executed. Full error message: Failed to connect to localhost/[0:0:0:0:0:0:0:1]:4317
+ERROR io.opentelemetry.exporter.internal.grpc.OkHttpGrpcExporter - Failed to export metrics. The request could not be executed. Full error message: Failed to connect to localhost/[0:0:0:0:0:0:0:1]:4317
+```
+
+#### Traces
+
+To turn off exporting of traces you can set `OTEL_TRACES_EXPORTER=none` as environment variable
+see [OpenTelemetry GitHub](https://github.com/open-telemetry/opentelemetry-java/tree/main/sdk-extensions/autoconfigure#otlp-exporter-span-metric-and-log-exporters).
+
+#### Metrics
+
+To turn off exporting of metrics you can set `OTEL_METRICS_EXPORTER=none` as environment variable
+see [OpenTelemetry GitHub](https://github.com/open-telemetry/opentelemetry-java/tree/main/sdk-extensions/autoconfigure#otlp-exporter-span-metric-and-log-exporters).

src/platform-includes/performance/opentelemetry-setup/with-java-agent/with-auto-init/debugging/java.mdx

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+To enable debug logging for Sentry, please provide `SENTRY_DEBUG=true` as environment variable or
+add `debug=true` to your `sentry.properties`.
+
+To also show debug output for OpenTelemetry please add `-Dotel.javaagent.debug=true` to the `java` command.

src/platform-includes/performance/opentelemetry-setup/with-java-agent/with-auto-init/java.mdx

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+This `java` command shows how to run your application using `sentry-opentelemetry-agent`:
+
+```bash
+SENTRY_PROPERTIES_FILE=sentry.properties java -javaagent:sentry-opentelemetry-agent-{{ packages.version('sentry.java.opentelemetry-agent') }}.jar -jar your-application.jar
+```
+
+Here's the `sentry.properties` file that goes with it:
+
+```properties {filename:sentry.properties}
+dsn=___DSN___
+traces-sample-rate=1.0
+```

src/platform-includes/performance/opentelemetry-setup/with-java-agent/without-auto-init/debugging/java.mdx

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+To enable debug logging for Sentry, please provide `SENTRY_DEBUG=true` as environment variable or
+add `debug=true` to your `sentry.properties`.
+
+To also show debug output for OpenTelemetry please add `-Dotel.javaagent.debug=true` to the `java` command.

src/platform-includes/performance/opentelemetry-setup/with-java-agent/without-auto-init/debugging/java.spring-boot.mdx

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+To enable debug logging for Sentry, please provide `SENTRY_DEBUG=true` as environment variable or
+add `sentry.debug=true` to your `application.properties`.
+
+To also show debug output for OpenTelemetry please add `-Dotel.javaagent.debug=true` to the command.

src/platform-includes/performance/opentelemetry-setup/with-java-agent/without-auto-init/java.mdx

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+If you are not using the auto initialization provided by `sentry-opentelemetry-agent` (`SENTRY_AUTO_INIT=false`) you have to set the `instrumenter` option to `otel`. This disables all Sentry instrumentation and relies on the chosen OpenTelemetry tracers for creating spans. You also have to add the `OpenTelemetryLinkErrorEventProcessor` to ensure errors are properly linked to transactions that were created by the OpenTelemetry integration:
+
+```java {tabTitle: Java}
+import io.sentry.Instrumenter;
+import io.sentry.Sentry;
+import io.sentry.opentelemetry.OpenTelemetryLinkErrorEventProcessor;
+
+Sentry.init(options -> {
+  options.setDsn("___PUBLIC_DSN___");
+  options.setTracesSampleRate(1.0);
+  options.setInstrumenter(Instrumenter.OTEL);
+  options.addEventProcessor(new OpenTelemetryLinkErrorEventProcessor());
+});
+```

src/platform-includes/performance/opentelemetry-setup/with-java-agent/without-auto-init/java.spring-boot.mdx

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+If you are not using the auto initialization provided by `sentry-opentelemetry-agent` (`SENTRY_AUTO_INIT=false`) you have to
+set the `instrumenter` option to `otel`. This disables all Sentry instrumentation and relies on the chosen OpenTelemetry tracers for creating spans.
+
+```properties {filename:application.properties}
+sentry.dsn=___DSN___
+sentry.traces-sample-rate=1.0
+# enable this to see more logs
+sentry.debug=false
+# set the instrumenter to use OpenTelemetry instead of Sentry
+sentry.instrumenter=otel
+```
+
+You also have to manually provide the `OpenTelemetryLinkErrorEventProcessor` bean to ensure errors are properly linked to transactions that were created by the OpenTelemetry integration:
+
+```java {filename:SentryDemoApplication.java}
+import io.sentry.opentelemetry.OpenTelemetryLinkErrorEventProcessor;
+
+@SpringBootApplication
+public class SentryDemoApplication {
+  public static void main(String[] args) {
+    SpringApplication.run(SentryDemoApplication.class, args);
+  }
+
+  ...
+
+  @Bean
+  OpenTelemetryLinkErrorEventProcessor otelLinkEventProcessor() {
+    return new OpenTelemetryLinkErrorEventProcessor();
+  }
+}
+```

src/platform-includes/performance/opentelemetry-setup/without-java-agent/java.mdx

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+#### Initializing OpenTelemetry
+
+```Java
+import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.context.propagation.ContextPropagators;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
+import io.opentelemetry.sdk.trace.SdkTracerProvider;
+
+import io.sentry.opentelemetry.SentryPropagator;
+import io.sentry.opentelemetry.SentrySpanProcessor;
+
+
+SdkTracerProvider sdkTracerProvider = SdkTracerProvider.builder()
+    .addSpanProcessor(new SentrySpanProcessor())
+    .build();
+
+OpenTelemetry openTelemetry = OpenTelemetrySdk.builder()
+    .setTracerProvider(sdkTracerProvider)
+    .setPropagators(ContextPropagators.create(new SentryPropagator()))
+    .buildAndRegisterGlobal();
+```
+
+#### Initializing Sentry
+
+You have to set the `instrumenter` option to `otel`. This disables all Sentry instrumentation and relies on the chosen OpenTelemetry tracers for creating spans. You also have to add the `OpenTelemetryLinkErrorEventProcessor` to ensure errors are properly linked to transactions that were created by the OpenTelemetry integration:
+
+```java {tabTitle: Java}
+import io.sentry.Instrumenter;
+import io.sentry.Sentry;
+import io.sentry.opentelemetry.OpenTelemetryLinkErrorEventProcessor;
+
+Sentry.init(options -> {
+  options.setDsn("___PUBLIC_DSN___");
+  options.setTracesSampleRate(1.0);
+  options.setInstrumenter(Instrumenter.OTEL);
+  options.addEventProcessor(new OpenTelemetryLinkErrorEventProcessor());
+});
+```

src/platform-includes/performance/opentelemetry-setup/without-java-agent/java.spring-boot.mdx

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+#### Initializing OpenTelemetry
+
+```Java
+import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.context.propagation.ContextPropagators;
+import io.opentelemetry.sdk.OpenTelemetrySdk;
+import io.opentelemetry.sdk.trace.SdkTracerProvider;
+
+import io.sentry.opentelemetry.SentryPropagator;
+import io.sentry.opentelemetry.SentrySpanProcessor;
+
+
+SdkTracerProvider sdkTracerProvider = SdkTracerProvider.builder()
+    .addSpanProcessor(new SentrySpanProcessor())
+    .build();
+
+OpenTelemetry openTelemetry = OpenTelemetrySdk.builder()
+    .setTracerProvider(sdkTracerProvider)
+    .setPropagators(ContextPropagators.create(new SentryPropagator()))
+    .buildAndRegisterGlobal();
+```
+
+#### Initializing Sentry
+
+You have to set the `instrumenter` option to `otel`. This disables all Sentry instrumentation and relies on the chosen OpenTelemetry tracers for creating spans.
+
+```properties {filename:application.properties}
+sentry.dsn=___DSN___
+sentry.traces-sample-rate=1.0
+# enable this to see more logs
+sentry.debug=false
+# set the instrumenter to use OpenTelemetry instead of Sentry
+sentry.instrumenter=otel
+```
+
+You also have to manually provide the `OpenTelemetryLinkErrorEventProcessor` bean to ensure errors are properly linked to transactions that were created by the OpenTelemetry integration:
+
+```java {filename:SentryDemoApplication.java}
+import io.sentry.opentelemetry.OpenTelemetryLinkErrorEventProcessor;
+
+@SpringBootApplication
+public class SentryDemoApplication {
+  public static void main(String[] args) {
+    SpringApplication.run(SentryDemoApplication.class, args);
+  }
+
+  ...
+
+  @Bean
+  OpenTelemetryLinkErrorEventProcessor otelLinkEventProcessor() {
+    return new OpenTelemetryLinkErrorEventProcessor();
+  }
+}
+```

src/platforms/java/common/performance/instrumentation/opentelemetry.mdx

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+---
+title: OpenTelemetry Support
+sidebar_order: 20
+description: "Using OpenTelemetry with Sentry Performance."
+---
+
+<Include name="alpha-note.mdx" />
+
+You can configure your [OpenTelemetry SDK](https://opentelemetry.io/) to send traces and spans to Sentry.
+
+There are multiple ways of combining OpenTelemetry and Sentry.
+
+## Using `sentry-opentelemetry-agent` with auto initialization
+
+By default, if you use `sentry-opentelemetry-agent`, it will look for `SENTRY_DSN` and `SENTRY_PROPERTIES_FILE` environment variables to be defined. If either of those is set, `sentry-opentelemetry-agent` will initialize Sentry automatically and you don't have to perform any setup work besides configuring your `DSN` and `tracesSampleRate`.
+
+### Install
+
+<PlatformContent includePath="performance/opentelemetry-install/with-java-agent" />
+
+### Usage
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/with-auto-init" />
+
+### Debugging
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/with-auto-init/debugging" />
+
+### Getting rid of exporter error messages
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/exporter-messages" />
+
+## Using `sentry-opentelemetry-agent` without auto initialization
+
+You may also disable automatic initialization of Sentry in `sentry-opentelemetry-agent` by setting `SENTRY_AUTO_INIT=false` as environment variable. This means you will either have to use another Sentry integration that performs initialization, for example Spring Boot, or initialize Sentry manually.
+
+### Install
+
+<PlatformContent includePath="performance/opentelemetry-install/with-java-agent" />
+
+### Usage
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/without-auto-init" />
+
+### Debugging
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/without-auto-init/debugging" />
+
+### Getting rid of exporter error messages
+
+<PlatformContent includePath="performance/opentelemetry-setup/with-java-agent/exporter-messages" />
+
+## Using OpenTelemetry without any Java Agent
+
+When manually initializing OpenTelemetry you have to register a few Sentry classes.
+
+### Install
+
+<PlatformContent includePath="performance/opentelemetry-install/without-java-agent" />
+
+### Usage
+
+<PlatformContent includePath="performance/opentelemetry-setup/without-java-agent" />