feat(palette): add Command dataclass and CommandRegistry

src/command_palette.py

@@ -0,0 +1,46 @@
+from __future__ import annotations
+from dataclasses import dataclass, field
+from typing import Optional, Callable, List, Dict, Any
+
+
+@dataclass
+class Command:
+    id: str
+    title: str
+    category: str
+    shortcut: Optional[str] = None
+    description: str = ""
+    enabled_when: Optional[str] = None
+    action: Optional[Callable] = None
+
+
+@dataclass
+class ScoredCommand:
+    command: Command
+    score: float
+
+
+class CommandRegistry:
+    def __init__(self) -> None:
+        self._commands: Dict[str, Command] = {}
+
+    def register(self, command_or_callable: Any) -> Any:
+        if isinstance(command_or_callable, Command):
+            cmd = command_or_callable
+        else:
+            cmd = Command(
+                id=command_or_callable.__name__,
+                title=command_or_callable.__name__.replace("_", " ").title(),
+                category="uncategorized",
+                action=command_or_callable,
+            )
+        if cmd.id in self._commands:
+            raise ValueError(f"Command {cmd.id} already registered")
+        self._commands[cmd.id] = cmd
+        return command_or_callable
+
+    def all(self) -> List[Command]:
+        return list(self._commands.values())
+
+    def get(self, command_id: str) -> Optional[Command]:
+        return self._commands.get(command_id)