Refactor project structure and enhance backend integration

- Expanded package inclusion in `pyproject.toml` to support new modules.
- Introduced new `adapters` and `protocol` packages for better organization.
- Added backend adapter implementations for control plane integration.
- Updated main application imports to reflect new package structure.
- Removed deprecated core components and adjusted documentation accordingly.
- Enhanced architecture documentation to clarify the new runtime and integration layers.

engine/runtime/pipeline/interrupts.py

@@ -0,0 +1,8 @@
+"""Interruption-related helpers extracted from the duplex pipeline."""
+
+from __future__ import annotations
+
+
+def should_interrupt(min_duration_ms: int, detected_ms: int) -> bool:
+    """Decide whether interruption conditions are met."""
+    return int(detected_ms) >= max(0, int(min_duration_ms))