refactor: extract ConversionCancelled to conversion_ports

- Single definition in application layer
- Both adapters import from ports instead of defining locally

abogen/application/conversion_ports.py

@@ -13,6 +13,11 @@ from dataclasses import dataclass
 from typing import Any, List, Optional, Protocol, runtime_checkable
 
 
+class ConversionCancelled(Exception):
+    """Raised when conversion is cancelled by user."""
+    pass
+
+
 class ConversionEvents(Protocol):
     """UI-specific actions the conversion service delegates back to the caller.
 

abogen/pyqt/conversion_adapter.py

@@ -18,7 +18,7 @@ from pathlib import Path
 from typing import Any, Callable, Dict, List, Optional
 
 from abogen.application.conversion_request import ConversionRequest
-from abogen.application.conversion_ports import ResolvedVoice
+from abogen.application.conversion_ports import ConversionCancelled, ResolvedVoice
 
 
 def build_conversion_request_from_thread(thread: Any) -> ConversionRequest:
@@ -135,11 +135,6 @@ class PyQtEvents:
             raise ConversionCancelled("Conversion cancelled by user")
 
 
-class ConversionCancelled(Exception):
-    """Raised when conversion is cancelled."""
-    pass
-
-
 class PyQtPipelineProvider:
     """PyQt implementation of PipelineProvider protocol.
 

abogen/webui/conversion_adapter.py

@@ -18,7 +18,7 @@ from pathlib import Path
 from typing import Any, Callable, Dict, List, Optional
 
 from abogen.application.conversion_request import ConversionRequest
-from abogen.application.conversion_ports import ResolvedVoice
+from abogen.application.conversion_ports import ConversionCancelled, ResolvedVoice
 
 
 def build_conversion_request_from_job(job: Any) -> ConversionRequest:
@@ -114,11 +114,6 @@ class WebJobEvents:
             raise ConversionCancelled("Job cancelled by user")
 
 
-class ConversionCancelled(Exception):
-    """Raised when conversion is cancelled."""
-    pass
-
-
 class WebPipelineProvider:
     """WebUI implementation of PipelineProvider protocol.