release: bump 0.8.4 -> 0.8.5 (#258)

Version bump `0.8.4` → `0.8.5`.

### Fixed
- The R binding's golden-fixture parity test now skips gracefully when the shared `testdata/golden` fixtures are not bundled with the package — standalone r-universe / CRAN builds package only `bindings/r`, so the repo-root fixtures are unreachable there (this was failing the r-universe build of 0.8.4). The parity stays enforced by the repository CI, where the fixtures are present. (#257)

Bump touches the manual release touchpoints only (`Cargo.toml`/`Cargo.lock`, Python/Node/Java/C#/R manifests, lockfiles, `SECURITY.md`, `CHANGELOG.md`). docs/webpage version strings are left to `sync-about.yml` on the tag.

examples/java/pom.xml

@@ -6,7 +6,7 @@
 
   <groupId>org.wickra.examples</groupId>
   <artifactId>wickra-examples</artifactId>
-  <version>0.8.4</version>
+  <version>0.8.5</version>
   <packaging>jar</packaging>
 
   <name>Wickra Java examples</name>
@@ -21,7 +21,7 @@
     <dependency>
       <groupId>org.wickra</groupId>
       <artifactId>wickra</artifactId>
-      <version>0.8.4</version>
+      <version>0.8.5</version>
     </dependency>
     <!-- Only the network examples (fetch_btcusdt) parse JSON. -->
     <dependency>