Add announcement for 3.7.3 release (#1838)

Author: WojciechMazur

_data/scala-releases.yml

@@ -1,7 +1,7 @@
 - category: current_version
   title: Current 3.7.x release
-  version: 3.7.2
-  release_date: August 1, 2025
+  version: 3.7.3
+  release_date: September 9, 2025
 - category: current_version
   title: Current 3.3.x LTS release
   version: 3.3.6

_downloads/2025-09-09-3.7.3.md

@@ -0,0 +1,10 @@
+---
+title: Scala 3.7.3
+start: 9 September 2025
+layout: downloadpage
+release_version: 3.7.3
+release_date: "September 9, 2025"
+permalink: /download/3.7.3.html
+license: <a href="https://www.scala-lang.org/license/">Apache License, Version 2.0</a>
+api_docs: https://www.scala-lang.org/api/3.7.3/
+---

_posts/2025-09-09-release-notes-3.7.3.md

@@ -0,0 +1,39 @@
+---
+category: release
+permalink: /news/3.7.3/
+title: "Scala 3.7.3 is now available!"
+by: Wojciech Mazur, VirtusLab
+---
+Scala 3.7.3 is now available!
+
+## Highlights of the release
+
+### Warn when an explicit `using` argument clouse with defaults shadows `given` in the scope [#23559](https://github.com/scala/scala3/pull/23559)
+
+If a call supplies any `using` argument explicitly, `given` search is not performed for the remaining params in that clause. If a remaining param has a default, that default is used, even if a compatible `given` is in scope. This behaviour could have been confusing for users and lead to unexpected problems at runtime. 
+The compiler now reports a warning when default argument would be used instead of given defined in the scope.
+```scala
+def f(using x: X, y: Y = defaultY) = ???
+given Y = ???
+f(using x = X()) // warns: y = defaultY
+```
+
+This change also adds new flag `-Wrecurse-with-default` to emit warning when a method calls itself using a default argument instead of forwarding the current value
+
+### Bump Scala CLI to v1.9.0
+  - Supports the new Scala 3 nightly Maven repository,
+  - Can be used to test Scala 3.8 nightly releases,
+  - See the [Scala CLI changelog](https://github.com/VirtusLab/scala-cli/releases/tag/v1.9.0) for additional details 
+
+### The new Maven repository for Scala 3 nightly releases
+
+  Scala 3 nightly releases are no longer published to Maven Central, these can now be found in dedicated `https://repo.scala-lang.org/artifactory/maven-nightlies` repository.
+
+  sbt 1.11.5 or later users can use a helper function to reference new repository in their builds
+  ```scala
+  resolvers += Resolver.scalaNightlyRepository
+  ```
+  
+
+
+For a full list of changes and contributor credits, please refer to the [release notes](https://github.com/scala/scala3/releases/tag/3.7.3).