[remote dev] rename subdirectories with JARs used by the split frontend process for consistency (IJPL-170362)

'client' directory is renamed to 'frontend-split' to be consistent with the actual naming schema. Consistent names are also needed to avoid changes in the layout when the JAR names for modules used by the split frontend process will be chosen automatically (IJPL-170362).

GitOrigin-RevId: 990d31cfae970579fa17119dd3869bb162b11923

java/plugin/plugin-content.yaml

@@ -1,9 +1,6 @@
 - name: lib/aether-dependency-resolver.jar
   modules:
   - name: intellij.java.aetherDependencyResolver
-- name: lib/client/java-frontend.jar
-  modules:
-  - name: intellij.java.frontend
 - name: lib/debugger-memory-agent.jar
 - name: lib/ecj/eclipse.jar
   projectLibraries:
@@ -11,6 +8,9 @@
     files:
     - name: $PROJECT_DIR$/community/lib/ecj-4.jar
     reason: withProjectLibrary
+- name: lib/frontend-split/java-frontend.jar
+  modules:
+  - name: intellij.java.frontend
 - name: lib/java-frontback.jar
   modules:
   - name: intellij.java.frontback.impl