Missing code action to add TODO to dictionary

**Describe the bug**
I don't want the string 'TODO' to be an error but I can't get rid of it

**To Reproduce**
Steps to reproduce the behavior:
1. Write a TODO in neovim
2. See that the word TODO is marked as an error by harper
3. Open list of code actions
4. Don't see option to add TODO to dictionary

**Expected behavior**
I use TODOs all the time and it's annoying that I can't just add it to my dictionary and never see the error again.

**Screenshots**


**Platform**
NVIM v0.10.2
Build type: RelWithDebInfo
LuaJIT 2.1.1720049189

harper 0.26.0

**Additional context**
Unsure if this is relevant at all, but this is a comment in a python file.

Reproduce the issue in Neovim 0.10.2 with harper 0.26.0 by placing TODO in a Python file and opening code actions. Trace the Neovim code-action path responsible for dictionary suggestions. Done means the code-action list offers adding TODO to the dictionary and the diagnostic no longer appears afterward.

Written by the indexing model from the issue text.