[VPAT-51] fix: update workspace invitation flow to use token for validation #8508

- Modified the invite link to include a token for enhanced security.
- Updated the WorkspaceJoinEndpoint to validate the token instead of the email.
- Adjusted the workspace invitation task to generate links with the token.
- Refactored the frontend to handle token in the invitation process.

Co-authored-by: sriram veeraghanta <veeraghanta.sriram@gmail.com>

apps/api/plane/app/serializers/workspace.py

@@ -111,7 +111,7 @@ class WorkSpaceMemberInviteSerializer(BaseSerializer):
     invite_link = serializers.SerializerMethodField()
 
     def get_invite_link(self, obj):
-        return f"/workspace-invitations/?invitation_id={obj.id}&email={obj.email}&slug={obj.workspace.slug}"
+        return f"/workspace-invitations/?invitation_id={obj.id}&slug={obj.workspace.slug}&token={obj.token}"
 
     class Meta:
         model = WorkspaceMemberInvite