Support data: in URL for memory. Add ootb support for pdfs (#67)

* support data: in URL for memory. Add ootb support for pdfs

* moved utility to common and updated data_url parsing logic

---------

Co-authored-by: Hardik Shah <hjshah@fb.com>

llama_toolchain/memory/common/file_utils.py

@@ -0,0 +1,26 @@
+# 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.
+
+import base64
+import mimetypes
+import os
+
+from llama_models.llama3.api.datatypes import URL
+
+
+def data_url_from_file(file_path: str) -> URL:
+    if not os.path.exists(file_path):
+        raise FileNotFoundError(f"File not found: {file_path}")
+
+    with open(file_path, "rb") as file:
+        file_content = file.read()
+
+    base64_content = base64.b64encode(file_content).decode("utf-8")
+    mime_type, _ = mimetypes.guess_type(file_path)
+
+    data_url = f"data:{mime_type};base64,{base64_content}"
+
+    return URL(uri=data_url)