Fix WebDAV lock database path (handler.rs)

Lock DB now uses data/webdav/{user}/.locks.sqlite
Server responds to GET/PROPFIND (HTTP 200 OK)

src/webdav/handler.rs

@@ -0,0 +1,31 @@
+use std::path::PathBuf;
+use dav_server::{DavHandler, localfs::LocalFs};
+use crate::webdav::lock_manager::LockManager;
+
+pub struct MarkBaseWebDAV {
+    user_id: String,
+    db_path: PathBuf,
+}
+
+impl MarkBaseWebDAV {
+    pub fn new(user_id: String, db_path: PathBuf) -> Self {
+        MarkBaseWebDAV { user_id, db_path }
+    }
+    
+    pub fn create_handler(&self) -> DavHandler {
+        let webdav_dir = format!("data/webdav/{}/", self.user_id);
+        let mount_point = PathBuf::from(&webdav_dir);
+        
+        std::fs::create_dir_all(&mount_point).expect("Failed to create WebDAV directory");
+        
+        let lock_db_path = mount_point.join(".locks.sqlite");
+        let lock_manager = LockManager::new(self.user_id.clone(), lock_db_path);
+        lock_manager.init_db().expect("Failed to initialize lock database");
+        
+        DavHandler::builder()
+            .filesystem(LocalFs::new(&mount_point, false, false, false))
+            .locksystem(Box::new(lock_manager))
+            .strip_prefix("/webdav")
+            .build_handler()
+    }
+}