Fix SpotBugs REC_CATCH_EXCEPTION: narrow exception catch in JsonRpcClient.handleMessage()

Co-authored-by: brunoborges <129743+brunoborges@users.noreply.github.com>

Author: Copilot

src/main/java/com/github/copilot/sdk/JsonRpcClient.java

@@ -306,7 +306,7 @@ else if (node.has("method")) {
                     }
                 }
             }
-        } catch (Exception e) {
+        } catch (JsonProcessingException e) {
             LOG.log(Level.SEVERE, "Error parsing JSON-RPC message", e);
         }
     }