chore: switch to src layout

src/lrx_cli/fetchers/base.py

@@ -0,0 +1,35 @@
+"""
+Author: Uyanide pywang0608@foxmail.com
+Date: 2026-03-25 02:33:26
+Description: Base fetcher class and common interfaces.
+"""
+
+from abc import ABC, abstractmethod
+from typing import Optional
+
+from ..models import TrackMeta, LyricResult
+
+
+class BaseFetcher(ABC):
+    @property
+    @abstractmethod
+    def source_name(self) -> str:
+        """Name of the fetcher source."""
+        pass
+
+    @property
+    def self_cached(self) -> bool:
+        """True if this fetcher manages its own cache (skip per-source cache check)."""
+        return False
+
+    @abstractmethod
+    def is_available(self, track: TrackMeta) -> bool:
+        """Check if the fetcher is available for the given track (e.g. has required metadata)."""
+        pass
+
+    @abstractmethod
+    async def fetch(
+        self, track: TrackMeta, bypass_cache: bool = False
+    ) -> Optional[LyricResult]:
+        """Fetch lyrics for the given track. Returns None if unable to fetch."""
+        pass