fix: add missing await for get_nextcloud_client in capabilities resource

Fix nc_get_capabilities resource handler that was missing await when
calling get_nextcloud_client(ctx), causing error:
'coroutine' object has no attribute 'capabilities'

Root cause:
- get_nextcloud_client() is an async function (context.py:9)
- Returns a coroutine that must be awaited
- app.py:737 called it without await

Solution:
- Add await: client = await get_nextcloud_client(ctx)
- The handler is already async, so can await the call

Test fixed:
- test_mcp_resources_access now passes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

nextcloud_mcp_server/app.py

@@ -734,7 +734,7 @@ def get_app(transport: str = "sse", enabled_apps: list[str] | None = None):
     async def nc_get_capabilities():
         """Get the Nextcloud Host capabilities"""
         ctx: Context = mcp.get_context()
-        client = get_nextcloud_client(ctx)
+        client = await get_nextcloud_client(ctx)
         return await client.capabilities()
 
     # Define available apps and their configuration functions