[Feature] Server pagination implementation (#243)

## Major Changes
- Implement a REST style API app in epapi
- Currently implements a GET method for all entity types in the browse menu (both package level and global)
- Provides paginated results per default with query style filtering for reviewed vs unreviewed.
- Provides new paginated templates with thin wrappers per entity types for easier maintainability
- Implements e2e tests for the API

## Minor changes
- Added more comprehensive gitignore to cover coverage reports and other test/node.js etc. data.
- Add additional CI file for API tests that only gets triggered on API relevant changes.

## ⚠️ Currently only works with session-based authentication. Token based will be added in new PR.

Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Co-authored-by: jebus <lorsbach@envipath.com>
Reviewed-on: enviPath/enviPy#243
Co-authored-by: Tobias O <tobias.olenyi@envipath.com>
Co-committed-by: Tobias O <tobias.olenyi@envipath.com>

epapi/v1/pagination.py

@@ -0,0 +1,60 @@
+import math
+from typing import Any, Generic, List, TypeVar
+
+from django.db.models import QuerySet
+from ninja import Schema
+from ninja.pagination import PageNumberPagination
+
+T = TypeVar("T")
+
+
+class EnhancedPageNumberPagination(PageNumberPagination):
+    class Output(Schema, Generic[T]):
+        items: List[T]
+        page: int
+        page_size: int
+        total_items: int
+        total_pages: int
+
+    def paginate_queryset(
+        self,
+        queryset: QuerySet,
+        pagination: PageNumberPagination.Input,
+        **params: Any,
+    ) -> Any:
+        page_size = self._get_page_size(pagination.page_size)
+        offset = (pagination.page - 1) * page_size
+        total_items = self._items_count(queryset)
+        total_pages = math.ceil(total_items / page_size) if page_size > 0 else 0
+
+        return {
+            "items": queryset[offset : offset + page_size],
+            "page": pagination.page,
+            "page_size": page_size,
+            "total_items": total_items,
+            "total_pages": total_pages,
+        }
+
+    async def apaginate_queryset(
+        self,
+        queryset: QuerySet,
+        pagination: PageNumberPagination.Input,
+        **params: Any,
+    ) -> Any:
+        page_size = self._get_page_size(pagination.page_size)
+        offset = (pagination.page - 1) * page_size
+        total_items = await self._aitems_count(queryset)
+        total_pages = math.ceil(total_items / page_size) if page_size > 0 else 0
+
+        if isinstance(queryset, QuerySet):
+            items = [obj async for obj in queryset[offset : offset + page_size]]
+        else:
+            items = queryset[offset : offset + page_size]
+
+        return {
+            "items": items,
+            "page": pagination.page,
+            "page_size": page_size,
+            "total_items": total_items,
+            "total_pages": total_pages,
+        }