Address PR review comments for UID2-5185

- Removed 'please' from all error messages per documentation standards
- Updated 'visit UID2 guides' to more specific wording
- Added documentation link: https://unifiedid.com/docs/guides/integration-options-private-operator
- Added E12 error code to CloudSyncVerticle.java (line 408)
- Fixed punctuation and sentence structure in error messages
- Updated test assertions to match new error message format

Author: lizk886

src/main/java/com/uid2/shared/attest/UidCoreClient.java

@@ -94,7 +94,7 @@ private InputStream internalDownload(String path) throws CloudStorageException {
         } catch (Exception e) {
             throw new CloudStorageException(
                 "E12: Data Download Failure - exception: " + e.getClass().getSimpleName() + 
-                ". Please visit UID2 guides for troubleshooting", e);
+                ". For troubleshooting information, refer to the applicable Private Operator guide: see https://unifiedid.com/docs/guides/integration-options-private-operator.", e);
         }
     }
 
@@ -113,7 +113,7 @@ private InputStream getWithAttest(String path) throws IOException, AttestationRe
         httpResponse = sendHttpRequest(path, attestationToken);
         if (httpResponse.statusCode() != 200) {
             throw new CloudStorageException(String.format(
-                "E12: Data Download Failure - HTTP response code %d. Please visit UID2 guides for troubleshooting", 
+                "E12: Data Download Failure - HTTP response code %d. For troubleshooting information, refer to the applicable Private Operator guide: see https://unifiedid.com/docs/guides/integration-options-private-operator.", 
                 httpResponse.statusCode()));
         }
         return Utils.convertHttpResponseToInputStream(httpResponse);

src/main/java/com/uid2/shared/cloud/URLStorageWithMetadata.java

@@ -49,7 +49,7 @@ public InputStream download(String cloudPath) throws CloudStorageException {
                 return httpConn.getInputStream();
             } else {
                 throw new CloudStorageException("E12: Data Download Failure - HTTP response code " + responseCode 
-                + ". Please visit UID2 guides for troubleshooting");
+                + ". For troubleshooting information, refer to the applicable Private Operator guide: see https://unifiedid.com/docs/guides/integration-options-private-operator.");
             }
         }
         catch (CloudStorageException e) {
@@ -59,7 +59,7 @@ public InputStream download(String cloudPath) throws CloudStorageException {
         catch (Throwable t) {
             // Do not log the original exception as it may contain sensitive information such as the pre-signed URL
             throw new CloudStorageException("E12: Data Download Failure - exception: " + t.getClass().getSimpleName() +
-                ". Please visit UID2 guides for troubleshooting");
+                ". For troubleshooting information, refer to the applicable Private Operator guide: see https://unifiedid.com/docs/guides/integration-options-private-operator.");
         }
     }
 

src/main/java/com/uid2/shared/vertx/CloudSyncVerticle.java

@@ -405,8 +405,8 @@ private void cloudDownloadBlocking(String s3Path) throws Exception {
             if (ex instanceof CloudStorageException) {
                 throw (CloudStorageException) ex;
             }
-            throw new CloudStorageException("Failed to download file from cloud storage, exception: " 
-                + ex.getClass().getSimpleName() + ", please check network connectivity and service availability"); 
+            throw new CloudStorageException("E12: Data Download Failure - Failed to download file from cloud storage, exception: " 
+                + ex.getClass().getSimpleName() + ". Check network connectivity and service availability."); 
         }
     }
 

src/test/java/com/uid2/shared/attest/UidCoreClientTest.java

@@ -72,7 +72,7 @@ public void Download_AttestInternalFail_ExceptionThrown() throws IOException, At
         CloudStorageException result = assertThrows(CloudStorageException.class, () -> {
             uidCoreClient.download("https://download");
         });
-        String expectedExceptionMessage = "E12: Data Download Failure - exception: AttestationResponseHandlerException. Please visit UID2 guides for troubleshooting";
+        String expectedExceptionMessage = "E12: Data Download Failure - exception: AttestationResponseHandlerException. For troubleshooting information, refer to the applicable Private Operator guide: see https://unifiedid.com/docs/guides/integration-options-private-operator.";
         assertEquals(expectedExceptionMessage, result.getMessage());
     }
 
@@ -116,7 +116,7 @@ public void Download_Http403Error_LogsStatusCodeAndEndpoint() throws IOException
                 "Should contain E12 error code"),
             () -> assertTrue(result.getMessage().contains("HTTP response code 403"), 
                 "Should contain HTTP status code 403"),
-            () -> assertTrue(result.getMessage().contains("Please visit UID2 guides for troubleshooting"), 
+            () -> assertTrue(result.getMessage().contains("For troubleshooting information, refer to the applicable Private Operator guide"), 
                 "Should reference documentation")
         );
     }
@@ -185,7 +185,7 @@ public void Download_NetworkError_LogsExceptionType() throws IOException, Attest
                 "Should contain E12 error code"),
             () -> assertTrue(result.getMessage().contains("exception: IOException"), 
                 "Should log exception type"),
-            () -> assertTrue(result.getMessage().contains("Please visit UID2 guides for troubleshooting"), 
+            () -> assertTrue(result.getMessage().contains("For troubleshooting information, refer to the applicable Private Operator guide"), 
                 "Should reference documentation")
         );
     }