v2.5.14: bump CosmoKv 3.2.0 → 3.2.1

CosmoKv 3.2.1 adds the cosmokv.write.queue_depth observable gauge so
downstream consumers can correlate writer-channel backpressure with
their own SLOs. No driver-side changes; this is purely a transitive
metric exposure.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: vkuttyp

src/CosmoSQLClient.CosmoKv/CosmoSQLClient.CosmoKv.csproj

@@ -5,7 +5,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="CosmoKv" Version="3.2.0" />
+    <PackageReference Include="CosmoKv" Version="3.2.1" />
     <!-- Microsoft.VisualStudio.Threading.AsyncReaderWriterLock — battle-
          tested writer-priority RW lock for the CosmoKvConnection
          hot path. The v2.5.7 attempt at rolling our own failed under