feat(eval api): (2.2/n) delete eval / scoring / scoring_fn apis (#1700)

# What does this PR do?
- To make it easier, delete existing `eval/scoring/scoring_function`
apis. There will be a bunch of broken impls here. The sequence is:
1. migrate benchmark graders
2. clean up existing scoring functions

- Add a skeleton evaluation impl to make tests pass. 

## Test Plan
tested in following PRs

[//]: # (## Documentation)

llama_stack/providers/utils/common/data_schema_validator.py

@@ -5,14 +5,12 @@
 # the root directory of this source tree.
 
 from enum import Enum
-from typing import Any, Dict, List
 
 from llama_stack.apis.common.type_system import (
     ChatCompletionInputType,
     CompletionInputType,
     StringType,
 )
-from llama_stack.distribution.datatypes import Api
 
 
 class ColumnName(Enum):
@@ -75,29 +73,31 @@ VALID_SCHEMAS_FOR_EVAL = [
 ]
 
 
-def get_valid_schemas(api_str: str):
-    if api_str == Api.scoring.value:
-        return VALID_SCHEMAS_FOR_SCORING
-    elif api_str == Api.eval.value:
-        return VALID_SCHEMAS_FOR_EVAL
-    else:
-        raise ValueError(f"Invalid API string: {api_str}")
+# TODO(xiyan): add this back
+
+# def get_valid_schemas(api_str: str):
+#     if api_str == Api.scoring.value:
+#         return VALID_SCHEMAS_FOR_SCORING
+#     elif api_str == Api.eval.value:
+#         return VALID_SCHEMAS_FOR_EVAL
+#     else:
+#         raise ValueError(f"Invalid API string: {api_str}")
 
 
-def validate_dataset_schema(
-    dataset_schema: Dict[str, Any],
-    expected_schemas: List[Dict[str, Any]],
-):
-    if dataset_schema not in expected_schemas:
-        raise ValueError(f"Dataset {dataset_schema} does not have a correct input schema in {expected_schemas}")
+# def validate_dataset_schema(
+#     dataset_schema: Dict[str, Any],
+#     expected_schemas: List[Dict[str, Any]],
+# ):
+#     if dataset_schema not in expected_schemas:
+#         raise ValueError(f"Dataset {dataset_schema} does not have a correct input schema in {expected_schemas}")
 
 
-def validate_row_schema(
-    input_row: Dict[str, Any],
-    expected_schemas: List[Dict[str, Any]],
-):
-    for schema in expected_schemas:
-        if all(key in input_row for key in schema):
-            return
+# def validate_row_schema(
+#     input_row: Dict[str, Any],
+#     expected_schemas: List[Dict[str, Any]],
+# ):
+#     for schema in expected_schemas:
+#         if all(key in input_row for key in schema):
+#             return
 
-    raise ValueError(f"Input row {input_row} does not match any of the expected schemas in {expected_schemas}")
+#     raise ValueError(f"Input row {input_row} does not match any of the expected schemas in {expected_schemas}")