feat(api): don't return a payload on file delete (#1640)

# What does this PR do?

This is to stay consistent with other APIs.

This change registers files in API, even though there are still no
providers. Removing tests that require a provider existing for a merged
API to enable it in API layer.

Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>

[//]: # (If resolving an issue, uncomment and update the line below)
[//]: # (Closes #[issue-number])

## Test Plan
[Describe the tests you ran to verify your changes with result
summaries. *Provide clear instructions so the plan can be easily
re-executed.*]

[//]: # (## Documentation)

Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>

llama_stack/apis/datatypes.py

@@ -34,6 +34,7 @@ class Api(Enum):
     scoring_functions = "scoring_functions"
     benchmarks = "benchmarks"
     tool_groups = "tool_groups"
+    files = "files"
 
     # built-in API
     inspect = "inspect"

llama_stack/apis/files/files.py

@@ -164,7 +164,7 @@ class Files(Protocol):
         self,
         bucket: str,
         key: str,
-    ) -> FileResponse:
+    ) -> None:
         """
         Delete a file identified by a bucket and key.
 

llama_stack/distribution/resolver.py

@@ -12,6 +12,7 @@ from llama_stack.apis.benchmarks import Benchmarks
 from llama_stack.apis.datasetio import DatasetIO
 from llama_stack.apis.datasets import Datasets
 from llama_stack.apis.eval import Eval
+from llama_stack.apis.files import Files
 from llama_stack.apis.inference import Inference
 from llama_stack.apis.inspect import Inspect
 from llama_stack.apis.models import Models
@@ -79,6 +80,7 @@ def api_protocol_map() -> Dict[Api, Any]:
         Api.post_training: PostTraining,
         Api.tool_groups: ToolGroups,
         Api.tool_runtime: ToolRuntime,
+        Api.files: Files,
     }
 
 

llama_stack/providers/registry/files.py

@@ -0,0 +1,11 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from llama_stack.providers.datatypes import ProviderSpec
+
+
+def available_providers() -> list[ProviderSpec]:
+    return []