Implement Upload Hook for momentry integration (Phase 1)

- Add upload_hook.rs module: trigger video_probe + video_register on upload
- Add UploadHookSection to config: video extensions, binary paths
- Integrate with SFTP: handle_close triggers hook on write files
- Integrate with SCP/rsync: child process exit triggers hook
- All 155 tests pass

markbase-core/src/ssh_server/sftp_handler.rs

@@ -289,6 +289,7 @@ pub struct SftpHandle {
     pub handle_type: SftpHandleType,
     pub file: Option<Box<dyn VfsFile>>,
     pub dir_entries: Option<Vec<VfsDirEntry>>,
+    pub write_mode: bool,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -303,10 +304,10 @@ pub struct SftpHandler {
     vfs: Box<dyn VfsBackend>,
     next_handle_id: u32,
     handles: std::collections::HashMap<u32, SftpHandle>,
-    // ⭐⭐⭐⭐⭐ Phase 4: 添加 client maxpack 限制（参考OpenSSH sftp-server.c）
-    maxpacket: u32, // 来自 SSH_MSG_CHANNEL_OPEN_CONFIRMATION 的 maximum_packet_size
-    /// 限制绝对路径也在 root_dir 之下（chroot 模式）
+    maxpacket: u32,
     restrict_absolute: bool,
+    upload_hook: Option<std::sync::Arc<crate::ssh_server::upload_hook::UploadHook>>,
+    user_uuid: String,
 }
 
 impl SftpHandler {
@@ -318,7 +319,13 @@ impl SftpHandler {
     const MAX_HASH_SIZE: u64 = 268_435_456;
 
     // ⭐⭐⭐⭐⭐ Phase 4: 修改 new() 方法，接受 maxpack 参数
-    pub fn new(root_dir: PathBuf, vfs: Box<dyn VfsBackend>, maxpacket: u32) -> Self {
+    pub fn new(
+        root_dir: PathBuf,
+        vfs: Box<dyn VfsBackend>,
+        maxpacket: u32,
+        upload_hook: Option<std::sync::Arc<crate::ssh_server::upload_hook::UploadHook>>,
+        user_uuid: String,
+    ) -> Self {
         let canonical_root = root_dir.canonicalize().unwrap_or(root_dir);
         Self {
             root_dir: canonical_root,
@@ -327,6 +334,8 @@ impl SftpHandler {
             handles: std::collections::HashMap::new(),
             maxpacket,
             restrict_absolute: false,
+            upload_hook,
+            user_uuid,
         }
     }
 
@@ -426,6 +435,7 @@ impl SftpHandler {
                     handle_type: SftpHandleType::File,
                     file: Some(file),
                     dir_entries: None,
+                    write_mode: flags.write,
                 };
 
                 self.handles.insert(handle_id, handle);
@@ -454,7 +464,14 @@ impl SftpHandler {
 
         info!("SSH_FXP_CLOSE: id={}, handle={}", id, handle_id);
 
-        if self.handles.remove(&handle_id).is_some() {
+        if let Some(handle) = self.handles.remove(&handle_id) {
+            if handle.write_mode && handle.handle_type == SftpHandleType::File {
+                if let Some(hook) = &self.upload_hook {
+                    if let Err(e) = hook.trigger(&handle.path, &self.user_uuid) {
+                        warn!("Upload hook failed for {:?}: {}", handle.path, e);
+                    }
+                }
+            }
             self.build_status_response(id, SftpStatus::SSH_FX_OK, "File closed")
         } else {
             self.build_status_response(id, SftpStatus::SSH_FX_FAILURE, "Invalid handle")
@@ -670,6 +687,7 @@ impl SftpHandler {
                     handle_type: SftpHandleType::Directory,
                     file: None,
                     dir_entries: Some(entries),
+                    write_mode: false,
                 };
 
                 self.handles.insert(handle_id, handle);
@@ -1765,7 +1783,7 @@ mod tests {
     use tempfile::TempDir;
 
     fn make_handler(root_dir: PathBuf) -> SftpHandler {
-        SftpHandler::new(root_dir, Box::new(LocalFs::new()), 32768)
+        SftpHandler::new(root_dir, Box::new(LocalFs::new()), 32768, None, "test_user".to_string())
     }
 
     #[test]