fix: update return type hints for RequestError factory methods

Signed-off-by: Frost Ming <me@frostming.com>

Author: frostming

src/acp/exceptions.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Any, Self
+from typing import Any
 
 __all__ = ["RequestError"]
 
@@ -14,31 +14,31 @@ def __init__(self, code: int, message: str, data: Any | None = None) -> None:
         self.data = data
 
     @classmethod
-    def parse_error(cls, data: dict[str, Any] | None = None) -> Self:
+    def parse_error(cls, data: dict[str, Any] | None = None) -> RequestError:
         return cls(-32700, "Parse error", data)
 
     @classmethod
-    def invalid_request(cls, data: dict[str, Any] | None = None) -> Self:
+    def invalid_request(cls, data: dict[str, Any] | None = None) -> RequestError:
         return cls(-32600, "Invalid request", data)
 
     @classmethod
-    def method_not_found(cls, method: str) -> Self:
+    def method_not_found(cls, method: str) -> RequestError:
         return cls(-32601, "Method not found", {"method": method})
 
     @classmethod
-    def invalid_params(cls, data: dict[str, Any] | None = None) -> Self:
+    def invalid_params(cls, data: dict[str, Any] | None = None) -> RequestError:
         return cls(-32602, "Invalid params", data)
 
     @classmethod
-    def internal_error(cls, data: dict[str, Any] | None = None) -> Self:
+    def internal_error(cls, data: dict[str, Any] | None = None) -> RequestError:
         return cls(-32603, "Internal error", data)
 
     @classmethod
-    def auth_required(cls, data: dict[str, Any] | None = None) -> Self:
+    def auth_required(cls, data: dict[str, Any] | None = None) -> RequestError:
         return cls(-32000, "Authentication required", data)
 
     @classmethod
-    def resource_not_found(cls, uri: str | None = None) -> Self:
+    def resource_not_found(cls, uri: str | None = None) -> RequestError:
         data = {"uri": uri} if uri is not None else None
         return cls(-32002, "Resource not found", data)