BUGFIX: Fix content cache for discard, revert neos#5083 for now

The change was taken too lightly and the whole content cache flushing depends on the assumption that after publishing or discard, everything will be rendered.
With this knowledge and the added test we should be able to refactor it correctly in the feature without introducing a regression again.

Neos.Neos/Classes/Fusion/Cache/NodeCacheEntryIdentifier.php

@@ -14,6 +14,7 @@
 
 namespace Neos\Neos\Fusion\Cache;
 
+use Neos\ContentRepository\Core\SharedModel\Workspace\ContentStreamId;
 use Neos\Flow\Annotations as Flow;
 use Neos\Cache\CacheAwareInterface;
 use Neos\ContentRepository\Core\Projection\ContentGraph\Node;
@@ -22,17 +23,18 @@
  * The cache entry identifier data transfer object for nodes
  *
  * @Flow\Proxy(false)
+ * @internal
  */
-final class NodeCacheEntryIdentifier implements CacheAwareInterface
+final readonly class NodeCacheEntryIdentifier implements CacheAwareInterface
 {
     private function __construct(
-        private readonly string $value
+        private string $value
     ) {
     }
 
-    public static function fromNode(Node $node): self
+    public static function fromNode(Node $node, ContentStreamId $contentStreamId): self
     {
-        return new self('Node_' . $node->workspaceName->value
+        return new self('Node_' . $contentStreamId->value
             . '_' . $node->dimensionSpacePoint->hash
             . '_' .  $node->aggregateId->value);
     }

Neos.Neos/Classes/Fusion/Helper/CachingHelper.php

@@ -19,6 +19,7 @@
 use Neos\ContentRepository\Core\Projection\ContentGraph\Nodes;
 use Neos\ContentRepository\Core\Projection\Workspace\Workspace;
 use Neos\ContentRepository\Core\SharedModel\Node\NodeAggregateId;
+use Neos\ContentRepository\Core\SharedModel\Workspace\ContentStreamId;
 use Neos\ContentRepositoryRegistry\ContentRepositoryRegistry;
 use Neos\Eel\ProtectedContextAwareInterface;
 use Neos\Flow\Annotations as Flow;
@@ -38,6 +39,11 @@ class CachingHelper implements ProtectedContextAwareInterface
      */
     protected $contentRepositoryRegistry;
 
+    /**
+     * @var array<string, ContentStreamId>
+     */
+    private array $workspaceNameToContentStreamIdMapping = [];
+
     /**
      * Generate a `@cache` entry tag for a single node, array of nodes or a FlowQuery result
      * A cache entry with this tag will be flushed whenever one of the
@@ -70,7 +76,11 @@ public function nodeTag(iterable|Node $nodes): array
      */
     public function entryIdentifierForNode(Node $node): NodeCacheEntryIdentifier
     {
-        return NodeCacheEntryIdentifier::fromNode($node);
+        // Todo adjust content caching to work with workspaces as entry identifier than the content stream id
+        $currentContentStreamId = $this->workspaceNameToContentStreamIdMapping[$node->contentRepositoryId->value . '@' . $node->workspaceName->value]
+            ??= $this->contentRepositoryRegistry->get($node->contentRepositoryId)->getContentGraph($node->workspaceName)->getContentStreamId();
+
+        return NodeCacheEntryIdentifier::fromNode($node, $currentContentStreamId);
     }
 
     /**