chore: add key recipe cache for routing (#4294)

* feat: add key recipe cache for routing

* chore: generate libraries at Tue Jan 20 09:37:42 UTC 2026

* incorporate changes

* fix javadoc

* chore: generate libraries at Wed Jan 28 07:48:52 UTC 2026

---------

Co-authored-by: cloud-java-bot <cloud-java-bot@google.com>

Author: rahul2393

README.md

@@ -19,7 +19,7 @@ If you are using Maven with [BOM][libraries-bom], add this to your pom.xml file:
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>libraries-bom</artifactId>
-      <version>26.72.0</version>
+      <version>26.74.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -41,7 +41,7 @@ If you are using Maven without the BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-spanner</artifactId>
-  <version>6.102.1</version>
+  <version>6.107.0</version>
 </dependency>
 
 ```

google-cloud-spanner/src/main/java/com/google/cloud/spanner/spi/v1/ChannelEndpointCache.java

@@ -43,19 +43,19 @@ public interface ChannelEndpointCache {
   ChannelEndpoint defaultChannel();
 
   /**
-   * Returns a cached server for the given address, creating it if needed.
+   * Returns a cached channel for the given address, creating it if needed.
    *
-   * <p>If a server for this address already exists in the cache, the cached instance is returned.
+   * <p>If a channel for this address already exists in the cache, the cached instance is returned.
    * Otherwise, a new server connection is created and cached.
    *
    * @param address the server address in "host:port" format
-   * @return a server instance for the address, never null
+   * @return a channel instance for the address, never null
    * @throws com.google.cloud.spanner.SpannerException if the channel cannot be created
    */
   ChannelEndpoint get(String address);
 
   /**
-   * Evicts a server from the cache and gracefully shuts down its channel.
+   * Evicts a server connection from the cache and gracefully shuts down its channel.
    *
    * <p>This method should be called when a server becomes unhealthy or is no longer needed. The
    * channel shutdown is graceful: existing RPCs are allowed to complete, but new RPCs will not be