refactor: remove deprecated parameter and function/cleanup code (#101)

* refactor: remove deprecated parameter and function

* refactor: centralize type aliases in types.py and simplify crud layer

* test: add missing tests for fixtures/utils.py

* refactor: simplify and deduplicate across crud, metrics, cli, and
exceptions

* docs: fix old Paginate references

* docs: add migration + fix icon

* docs: update README/migration to v2

src/fastapi_toolsets/schemas.py

@@ -1,24 +1,23 @@
 """Base Pydantic schemas for API responses."""
 
 from enum import Enum
-from typing import Any, ClassVar, Generic, TypeVar
+from typing import Any, ClassVar, Generic
 
 from pydantic import BaseModel, ConfigDict
 
+from .types import DataT
+
 __all__ = [
     "ApiError",
     "CursorPagination",
     "ErrorResponse",
     "OffsetPagination",
-    "Pagination",
     "PaginatedResponse",
     "PydanticBase",
     "Response",
     "ResponseStatus",
 ]
 
-DataT = TypeVar("DataT")
-
 
 class PydanticBase(BaseModel):
     """Base class for all Pydantic models with common configuration."""
@@ -108,10 +107,6 @@ class OffsetPagination(PydanticBase):
     has_more: bool
 
 
-# Backward-compatible - will be removed in v2.0
-Pagination = OffsetPagination
-
-
 class CursorPagination(PydanticBase):
     """Pagination metadata for cursor-based list responses.