feat: add all_files iterator to simplify searching

Signed-off-by: Konstantin Fickel <mail@konstantinfickel.de>

src/streamer/parse/attach_markdown.py

@@ -0,0 +1,31 @@
+from streamer.parse.shard import Shard, StreamFile
+
+
+class ShardWithMarkdown(Shard):
+    children: list[ShardWithMarkdown]
+    markdown_content: str
+
+
+class StreamFileWithMarkdown(StreamFile):
+    shard: ShardWithMarkdown | None = None  # pyright: ignore[reportIncompatibleVariableOverride]
+
+
+def attach_markdown_shard(shard: Shard, markdown_text: str) -> ShardWithMarkdown:
+    lines = markdown_text.splitlines()
+    markdown_content = "\n".join(lines[shard.start_line - 1 : shard.end_line])
+    return ShardWithMarkdown(
+        **shard.model_dump(exclude=["children"]),
+        children=map(lambda child: attach_markdown_shard(child, markdown_text), shard.children),
+        markdown_content=markdown_content,
+    )
+
+
+def attach_markdown(file: StreamFile, markdown_text: str) -> StreamFileWithMarkdown:
+    if file.shard is None:
+        return StreamFileWithMarkdown(filename=file.filename, shard=None)
+
+    attached_shard = attach_markdown_shard(file.shard, markdown_text)
+    return StreamFileWithMarkdown(filename=file.filename, shard=attached_shard)
+
+
+__all__ = ["attach_markdown"]