Bump version to 0.6.5 and enhance update download functionality

- Updated version number in __init__.py to 0.6.5.
- Modified the download_update method in updater.py to accept a progress_callback for tracking download progress.
- Implemented chunked downloading in _download_file to report progress via the callback.
- Adjusted installer launching logic in updater.py to handle MSI files correctly using msiexec.
- Connected download progress signal in main_window.py to update the downloading dialog.

src/webdrop_bridge/core/updater.py

@@ -238,7 +238,7 @@ class UpdateManager:
             return None
 
     async def download_update(
-        self, release: Release, output_dir: Optional[Path] = None
+        self, release: Release, output_dir: Optional[Path] = None, progress_callback=None
     ) -> Optional[Path]:
         """Download installer from release assets.
 
@@ -279,6 +279,7 @@ class UpdateManager:
                     self._download_file,
                     installer_asset["browser_download_url"],
                     output_file,
+                    progress_callback,
                 ),
                 timeout=300,
             )
@@ -299,12 +300,13 @@ class UpdateManager:
                 output_file.unlink()
             return None
 
-    def _download_file(self, url: str, output_path: Path) -> bool:
+    def _download_file(self, url: str, output_path: Path, progress_callback=None) -> bool:
         """Download file from URL (blocking).
 
         Args:
             url: URL to download from
             output_path: Path to save file
+            progress_callback: Optional callable(bytes_downloaded, total_bytes)
 
         Returns:
             True if successful, False otherwise
@@ -312,8 +314,21 @@ class UpdateManager:
         try:
             logger.debug(f"Downloading from {url}")
             with urlopen(url, timeout=300) as response:  # 5 min timeout
+                total = int(response.headers.get("Content-Length", 0))
+                downloaded = 0
+                chunk_size = 65536  # 64 KB chunks
                 with open(output_path, "wb") as f:
-                    f.write(response.read())
+                    while True:
+                        chunk = response.read(chunk_size)
+                        if not chunk:
+                            break
+                        f.write(chunk)
+                        downloaded += len(chunk)
+                        if progress_callback:
+                            try:
+                                progress_callback(downloaded, total)
+                            except Exception:
+                                pass  # Never let progress errors abort the download
             logger.debug(f"Downloaded {output_path.stat().st_size} bytes")
             return True
         except URLError as e:
@@ -421,9 +436,12 @@ class UpdateManager:
             import subprocess
 
             if platform.system() == "Windows":
-                # Windows: Run MSI installer
+                # Windows: MSI files must be launched via msiexec
                 logger.info(f"Launching installer: {installer_path}")
-                subprocess.Popen([str(installer_path)])
+                if str(installer_path).lower().endswith(".msi"):
+                    subprocess.Popen(["msiexec.exe", "/i", str(installer_path)])
+                else:
+                    subprocess.Popen([str(installer_path)])
                 return True
             elif platform.system() == "Darwin":
                 # macOS: Mount DMG and run installer