[release] Prepare release core-1.13.0 (#6546)

Co-authored-by: opentelemetrybot <107717825+opentelemetrybot@users.noreply.github.com>

Author: otelbot-dotnet[bot]

RELEASENOTES.md

@@ -4,6 +4,16 @@ This file contains highlights and announcements covering all components.
 For more details see `CHANGELOG.md` files maintained in the root source
 directory of each individual package.
 
+## 1.13.0
+
+Release details: [1.13.0](https://github.com/open-telemetry/opentelemetry-dotnet/releases/tag/core-1.13.0)
+
+* gRPC calls to export traces, logs, and metrics using `OtlpExportProtocol.Grpc`
+  now set the `TE=trailers` HTTP request header to improve interoperability.
+* `EventName` is now exported by default as `EventName` instead of
+  `logrecord.event.name` when specified through `ILogger` or the experimental
+  log bridge API.
+
 ## 1.12.0
 
 Release details: [1.12.0](https://github.com/open-telemetry/opentelemetry-dotnet/releases/tag/core-1.12.0)

src/OpenTelemetry.Api.ProviderBuilderExtensions/CHANGELOG.md

@@ -7,6 +7,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 ## 1.12.0
 
 Released 2025-Apr-29

src/OpenTelemetry.Api/.publicApi/Stable/PublicAPI.Shipped.txt

@@ -126,6 +126,8 @@ OpenTelemetry.Trace.TelemetrySpan.AddEvent(string! name, OpenTelemetry.Trace.Spa
 OpenTelemetry.Trace.TelemetrySpan.AddEvent(string! name, System.DateTimeOffset timestamp, OpenTelemetry.Trace.SpanAttributes? attributes) -> OpenTelemetry.Trace.TelemetrySpan!
 OpenTelemetry.Trace.TelemetrySpan.AddEvent(string! name, System.DateTimeOffset timestamp) -> OpenTelemetry.Trace.TelemetrySpan!
 OpenTelemetry.Trace.TelemetrySpan.AddEvent(string! name) -> OpenTelemetry.Trace.TelemetrySpan!
+OpenTelemetry.Trace.TelemetrySpan.AddLink(OpenTelemetry.Trace.SpanContext spanContext, OpenTelemetry.Trace.SpanAttributes? attributes) -> OpenTelemetry.Trace.TelemetrySpan!
+OpenTelemetry.Trace.TelemetrySpan.AddLink(OpenTelemetry.Trace.SpanContext spanContext) -> OpenTelemetry.Trace.TelemetrySpan!
 OpenTelemetry.Trace.TelemetrySpan.Context.get -> OpenTelemetry.Trace.SpanContext
 OpenTelemetry.Trace.TelemetrySpan.Dispose() -> void
 OpenTelemetry.Trace.TelemetrySpan.End() -> void

src/OpenTelemetry.Api/.publicApi/Stable/PublicAPI.Unshipped.txt

@@ -1,2 +0,0 @@
-OpenTelemetry.Trace.TelemetrySpan.AddLink(OpenTelemetry.Trace.SpanContext spanContext) -> OpenTelemetry.Trace.TelemetrySpan!
-OpenTelemetry.Trace.TelemetrySpan.AddLink(OpenTelemetry.Trace.SpanContext spanContext, OpenTelemetry.Trace.SpanAttributes? attributes) -> OpenTelemetry.Trace.TelemetrySpan!

src/OpenTelemetry.Api/CHANGELOG.md

@@ -6,6 +6,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 * Added `AddLink(SpanContext, SpanAttributes?)` to `TelemetrySpan` to support
   linking spans and associating optional attributes for advanced trace relationships.
   ([#6305](https://github.com/open-telemetry/opentelemetry-dotnet/pull/6305))

src/OpenTelemetry.Exporter.Console/CHANGELOG.md

@@ -6,6 +6,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 ## 1.12.0
 
 Released 2025-Apr-29

src/OpenTelemetry.Exporter.InMemory/CHANGELOG.md

@@ -6,6 +6,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 ## 1.12.0
 
 Released 2025-Apr-29

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/CHANGELOG.md

@@ -7,6 +7,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 * Fixed an issue in .NET Framework where OTLP export of traces, logs, and
   metrics using `OtlpExportProtocol.Grpc` did not correctly set the initial
   write position, resulting in gRPC protocol errors.

src/OpenTelemetry.Exporter.Zipkin/CHANGELOG.md

@@ -6,6 +6,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 * Removed the peer service resolver, which was based on earlier experimental
   semantic conventions that are not part of the stable specification. This
   change ensures that the exporter no longer modifies or assumes the value of

src/OpenTelemetry.Extensions.Hosting/CHANGELOG.md

@@ -6,6 +6,10 @@ Notes](../../RELEASENOTES.md).
 
 ## Unreleased
 
+## 1.13.0
+
+Released 2025-Oct-01
+
 ## 1.12.0
 
 Released 2025-Apr-29