feat: added SynchronousExportingMetricReader

Author: Jayclifford345

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Add SynchronousExportingMetricReader for on-demand batch metric export without background threads
+  ([#XXXX](https://github.com/open-telemetry/opentelemetry-python/pull/XXXX))
+
 ## Version 1.32.0/0.53b0 (2025-04-10)
 
 - Fix user agent in OTLP HTTP metrics exporter
@@ -1730,7 +1733,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - Initial release api/sdk
-
 - Use Attribute rather than boundattribute in logrecord
   ([#3567](https://github.com/open-telemetry/opentelemetry-python/pull/3567))
 - Fix flush error when no LoggerProvider configured for LoggingHandler
@@ -1787,3 +1789,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#3778](https://github.com/open-telemetry/opentelemetry-python/pull/3778))
 - Fix license field in pyproject.toml files
   ([#3803](https://github.com/open-telemetry/opentelemetry-python/pull/3803))
+