feat(slack): adds canvas support for Slack channels (#6205)

Author: whitdog47

src/dispatch/__init__.py

@@ -79,6 +79,7 @@
     from dispatch.forms.type.models import FormsType  # noqa lgtm[py/unused-import]
     from dispatch.forms.models import Forms  # noqa lgtm[py/unused-import]
     from dispatch.email_templates.models import EmailTemplates  # noqa lgtm[py/unused-import]
+    from dispatch.canvas.models import Canvas  # noqa lgtm[py/unused-import]
 
 
 except Exception:

src/dispatch/canvas/__init__.py

@@ -0,0 +1,39 @@
+"""Canvas management module for Dispatch."""
+
+from .enums import CanvasType
+from .models import Canvas, CanvasBase, CanvasCreate, CanvasRead, CanvasUpdate
+from .service import (
+    create,
+    delete,
+    delete_by_slack_canvas_id,
+    get,
+    get_by_canvas_id,
+    get_by_case,
+    get_by_incident,
+    get_by_project,
+    get_by_type,
+    get_or_create_by_case,
+    get_or_create_by_incident,
+    update,
+)
+
+__all__ = [
+    "Canvas",
+    "CanvasBase",
+    "CanvasCreate",
+    "CanvasRead",
+    "CanvasType",
+    "CanvasUpdate",
+    "create",
+    "delete",
+    "delete_by_slack_canvas_id",
+    "get",
+    "get_by_canvas_id",
+    "get_by_case",
+    "get_by_incident",
+    "get_by_project",
+    "get_by_type",
+    "get_or_create_by_case",
+    "get_or_create_by_incident",
+    "update",
+]

src/dispatch/canvas/enums.py

@@ -0,0 +1,10 @@
+from dispatch.enums import DispatchEnum
+
+
+class CanvasType(DispatchEnum):
+    """Types of canvases that can be created."""
+
+    summary = "summary"
+    tactical_reports = "tactical_reports"
+    participants = "participants"
+    tasks = "tasks"