feat(fs): delegate win --server file reading to CM (#13736)

- Route Windows server-to-client file reads through CM instead of the connection layer
- Add FS IPC commands (ReadFile, CancelRead, SendConfirmForRead, ReadAllFiles) and CM data messages
  (ReadJobInitResult, FileBlockFromCM, FileReadDone, FileReadError, FileDigestFromCM, AllFilesResult)
- Track pending read validations and read jobs to coordinate CM-driven file transfers and clean them up
  on completion, cancellation, and errors
- Enforce a configurable file-transfer-max-files limit for ReadAllFiles and add stronger file name/path
  validation on the CM side
- Improve Flutter file transfer UX and robustness:
  - Use explicit percent/percentText progress fields
  - Derive speed and cancel actions from the active job
  - Handle job errors via FileModel.handleJobError and complete pending recursive tasks on failure
  - Wrap recursive directory operations in try/catch and await sendRemoveEmptyDir when removing empty directories

Signed-off-by: fufesou <linlong1266@gmail.com>

src/common.rs

@@ -181,6 +181,18 @@ pub fn is_server() -> bool {
     *IS_SERVER
 }
 
+#[inline]
+pub fn need_fs_cm_send_files() -> bool {
+    #[cfg(windows)]
+    {
+        is_server()
+    }
+    #[cfg(not(windows))]
+    {
+        false
+    }
+}
+
 #[inline]
 pub fn is_main() -> bool {
     *IS_MAIN