fix(05): cloud API path param, root sentinel, webdav creds in list, upload path

cloud.py: list_connections now decrypts and surfaces server_url +
connection_username for nextcloud/webdav providers; folder route uses
{folder_id:path} to handle slashes; translates "root" sentinel to "".
nextcloud_backend.py: skip parent directory entry in PROPFIND Depth:1 results.
webdav_backend.py: add cloud_folder + original_filename params to
upload_object so files land in the user's chosen folder with their real name.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/api/cloud.py

@@ -639,7 +639,19 @@ async def list_connections(
         select(CloudConnection).where(CloudConnection.user_id == current_user.id)
     )
     connections = result.scalars().all()
-    return {"items": [CloudConnectionOut.model_validate(c).model_dump() for c in connections]}
+    items = []
+    master_key = settings.cloud_creds_key.encode()
+    for conn in connections:
+        d = CloudConnectionOut.model_validate(conn).model_dump()
+        if conn.provider in ("nextcloud", "webdav"):
+            try:
+                creds = decrypt_credentials(master_key, str(conn.user_id), conn.credentials_enc)
+                d["server_url"] = creds.get("server_url")
+                d["connection_username"] = creds.get("username")
+            except Exception:
+                pass
+        items.append(d)
+    return {"items": items}
 
 
 # ── GET /api/cloud/connections/{connection_id}/config ────────────────────────
@@ -741,7 +753,7 @@ async def delete_connection(
 # ── GET /api/cloud/folders/{provider}/{folder_id} ─────────────────────────────
 
 
-@router.get("/folders/{provider}/{folder_id}")
+@router.get("/folders/{provider}/{folder_id:path}")
 async def list_cloud_folders(
     provider: str,
     folder_id: str,
@@ -874,9 +886,11 @@ async def list_cloud_folders(
 
     elif provider in ("nextcloud", "webdav"):
         backend = _build_backend(provider, credentials)
+        # "root" is a frontend sentinel meaning the WebDAV root; translate to ""
+        webdav_path = "" if folder_id == "root" else folder_id
 
         async def fetch_webdav() -> list:
-            return await backend.list_folder(folder_id)
+            return await backend.list_folder(webdav_path)
 
         items = await get_cloud_folders_cached(
             str(current_user.id), provider, folder_id, fetch_webdav

backend/storage/nextcloud_backend.py

@@ -93,11 +93,15 @@ class NextcloudBackend(WebDAVBackend):
         # client.list() returns a list of file/folder names in the directory
         items = await asyncio.to_thread(self._client.list, folder_path)
 
+        folder_norm = folder_path.strip("/")
         result: list[dict] = []
         for name in items:
-            # Skip the "." self-reference that some WebDAV servers include
+            # Skip the "." self-reference and empty entries
             if not name or name in (".", "./"):
                 continue
+            # Skip the directory itself (PROPFIND Depth:1 always includes the parent)
+            if name.strip("/") == folder_norm:
+                continue
 
             # Construct the full path for info lookup
             if folder_path:

backend/storage/webdav_backend.py

@@ -30,6 +30,7 @@ from __future__ import annotations
 import asyncio
 import io
 import urllib.parse
+from pathlib import Path
 
 from webdav3.client import Client
 
@@ -96,31 +97,25 @@ class WebDAVBackend(StorageBackend):
         file_bytes: bytes,
         extension: str,
         content_type: str,
+        cloud_folder: str | None = None,
+        original_filename: str | None = None,
     ) -> str:
         """Upload bytes to WebDAV and return the object_key (WebDAV path).
 
-        Ensures the parent directory "docuvault/{user_id}/" exists before upload
-        by calling client.mkdir() with recursive=True. webdavclient3 mkdir is a
-        no-op if the directory already exists.
-
-        Args:
-            user_id:      User UUID string.
-            document_id:  Document UUID string.
-            file_bytes:   Raw file content.
-            extension:    File extension with leading dot (e.g. ".pdf").
-            content_type: MIME type (unused by WebDAV, kept for ABC compliance).
-
-        Returns:
-            object_key: The WebDAV path where the file was stored.
-
-        Raises:
-            ValueError: If SSRF guard fires on re-validation (D-17).
+        When cloud_folder is provided the file is stored inside that folder
+        (e.g. "Documents/") using the original filename so it appears naturally
+        in the user's cloud folder browser. When omitted the default
+        DocuVault-managed UUID path is used.
         """
-        # Re-validate before every outbound request (D-17 / T-05-04-02)
         validate_cloud_url(self._server_url)
-        object_key = self._make_path(user_id, document_id, extension)
-        # Ensure parent directory exists (idempotent)
-        parent_dir = f"docuvault/{urllib.parse.quote(str(user_id), safe='')}"
+        if cloud_folder:
+            parent_dir = cloud_folder.rstrip("/")
+            # Use original filename (basename only — path traversal guard)
+            safe_name = Path(original_filename).name if original_filename else f"{document_id}{extension}"
+            object_key = f"{parent_dir}/{safe_name}" if parent_dir else safe_name
+        else:
+            object_key = self._make_path(user_id, document_id, extension)
+            parent_dir = f"docuvault/{urllib.parse.quote(str(user_id), safe='')}"
         await asyncio.to_thread(self._client.mkdir, parent_dir, True)
         buf = io.BytesIO(file_bytes)
         await asyncio.to_thread(self._client.upload_to, buf, object_key)