Fix EMPTY mode validation, hook null-checks, and Javadoc accuracy

.lastmerge

@@ -1 +1 @@
-f4d22d70016c377881d86e4c77f8a3f93746ffae
+60104052cd914949ddf8c7a31e1856cd6db0a57c

pom.xml

@@ -7,7 +7,7 @@
 
     <groupId>com.github</groupId>
     <artifactId>copilot-sdk-java</artifactId>
-    <version>1.0.0-beta-java.5-SNAPSHOT</version>
+    <version>1.0.0-beta-8-java.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>GitHub Copilot SDK :: Java</name>
@@ -94,7 +94,7 @@
             reference-impl-sync workflow and deal with the subsequent
             PR.
         -->
-        <readonly-copilot-sdk-ref-impl-version-from-lastmerge-file-updated-by-reference-impl-sync>^1.0.52-1</readonly-copilot-sdk-ref-impl-version-from-lastmerge-file-updated-by-reference-impl-sync>
+        <readonly-copilot-sdk-ref-impl-version-from-lastmerge-file-updated-by-reference-impl-sync>^1.0.55-5</readonly-copilot-sdk-ref-impl-version-from-lastmerge-file-updated-by-reference-impl-sync>
 
     </properties>
 

scripts/codegen/package.json

@@ -7,7 +7,7 @@
     "generate:java": "tsx java.ts"
   },
   "dependencies": {
-    "@github/copilot": "^1.0.52-1",
+    "@github/copilot": "^1.0.55-5",
     "json-schema": "^0.4.0",
     "tsx": "^4.20.6"
   }