[OPIK-2940] [FE][BE][DOCS] Video: Add support for Video LLM-as-a-judge, Datasets and Playground - WIP DO NOT MERGE

apps/opik-backend/src/main/java/com/comet/opik/api/ModelCostData.java

@@ -13,5 +13,6 @@ public record ModelCostData(String litellmProvider,
         String outputCostPerToken,
         String cacheCreationInputTokenCost,
         String cacheReadInputTokenCost,
-        boolean supportsVision) {
+        boolean supportsVision,
+        boolean supportsVideoInput) {
 }

apps/opik-backend/src/main/java/com/comet/opik/api/resources/v1/events/OnlineScoringLlmAsJudgeScorer.java

@@ -79,7 +79,8 @@ protected void score(@NonNull TraceToScoreLlmAsJudge message) {
                 String modelName = message.llmAsJudgeCode().model().name();
                 var llmProvider = llmProviderFactory.getLlmProvider(modelName);
                 var strategy = StructuredOutputStrategy.getStrategy(llmProvider, modelName);
-                scoreRequest = OnlineScoringEngine.prepareLlmRequest(message.llmAsJudgeCode(), trace, strategy);
+                scoreRequest = OnlineScoringEngine.prepareLlmRequest(message.llmAsJudgeCode(), trace, strategy,
+                        llmProvider);
             } catch (Exception exception) {
                 userFacingLogger.error("Error preparing LLM request for traceId '{}': \n\n{}",
                         trace.id(), exception.getMessage());

apps/opik-backend/src/main/java/com/comet/opik/api/resources/v1/events/OnlineScoringTraceThreadLlmAsJudgeScorer.java

@@ -167,7 +167,7 @@ private void processScoring(TraceThreadToScoreLlmAsJudge message, List<Trace> tr
             String modelName = message.code().model().name();
             var llmProvider = llmProviderFactory.getLlmProvider(modelName);
             var strategy = StructuredOutputStrategy.getStrategy(llmProvider, modelName);
-            scoreRequest = OnlineScoringEngine.prepareThreadLlmRequest(message.code(), traces, strategy);
+            scoreRequest = OnlineScoringEngine.prepareThreadLlmRequest(message.code(), traces, strategy, llmProvider);
         } catch (Exception exception) {
             userFacingLogger.error("Error preparing LLM request for threadId: '{}': \n\n{}",
                     threadId, exception.getMessage());

apps/opik-backend/src/main/java/com/comet/opik/domain/DatasetItemResultMapper.java

@@ -185,10 +185,29 @@ static Map<String, String> getOrDefault(Map<String, JsonNode> data) {
                 .stream()
                 .map(Map::entrySet)
                 .flatMap(Collection::stream)
-                .map(entry -> Map.entry(entry.getKey(), entry.getValue().toString()))
+                .map(entry -> Map.entry(entry.getKey(), jsonNodeToString(entry.getValue())))
                 .collect(toMap(Map.Entry::getKey, Map.Entry::getValue));
     }
 
+    /**
+     * Converts a JsonNode to its string representation without double-escaping.
+     * For TextNodes, returns the raw text value. For other node types, serializes to JSON.
+     *
+     * @param node The JsonNode to convert
+     * @return The string representation
+     */
+    private static String jsonNodeToString(JsonNode node) {
+        if (node == null || node.isNull()) {
+            return "";
+        }
+        // For text nodes, extract the raw text value without additional JSON serialization
+        if (node.isTextual()) {
+            return node.asText();
+        }
+        // For other node types (objects, arrays, numbers, booleans), serialize to JSON
+        return JsonUtils.writeValueAsString(node);
+    }
+
     static String getOrDefault(UUID value) {
         return Optional.ofNullable(value).map(UUID::toString).orElse("");
     }

apps/opik-backend/src/main/java/com/comet/opik/domain/llm/ChatCompletionService.java

@@ -94,6 +94,7 @@ public void createAndStreamResponse(
     public ChatResponse scoreTrace(@NonNull ChatRequest chatRequest,
             @NonNull LlmAsJudgeModelParameters modelParameters,
             @NonNull String workspaceId) {
+        // Standard path for non-multimodal or non-custom-LLM providers
         var languageModelClient = llmProviderFactory.getLanguageModel(workspaceId, modelParameters);
 
         ChatResponse chatResponse;