fix(model-client): memory leak in VersionChangeDetector

VersionChangeDetector wasn't disposed, while waiting for a change.
It was transitively calling runBlocking from a coroutine which means a
cancellation of the coroutine has no effect while being blocked.

Author: slisson

model-client/src/jvmMain/kotlin/org/modelix/model/client/RestWebModelClient.kt

@@ -371,7 +371,7 @@ class RestWebModelClient @JvmOverloads constructor(
         return runBlocking { getA(key) }
     }
 
-    suspend fun getA(key: String): String? {
+    override suspend fun getA(key: String): String? {
         val isHash = HashUtil.isSha256(key)
         if (isHash) {
             if (LOG.isDebugEnabled) {

model-client/src/jvmMain/kotlin/org/modelix/model/client/VersionChangeDetector.kt

@@ -69,7 +69,7 @@ abstract class VersionChangeDetector(
             store.listen(key, keyListener)
             while (isActive) {
                 try {
-                    val version = store[key]
+                    val version = store.getA(key)
                     if (version != lastVersionHash) {
                         LOG.debug { "New version detected by polling: $version" }
                         versionChanged(version)

model-datastructure/src/commonMain/kotlin/org/modelix/model/IKeyValueStore.kt

@@ -17,6 +17,7 @@ package org.modelix.model
 
 interface IKeyValueStore {
     operator fun get(key: String): String?
+    suspend fun getA(key: String): String? = get(key)
     fun put(key: String, value: String?)
     fun getAll(keys: Iterable<String>): Map<String, String?>
     fun putAll(entries: Map<String, String?>)