Teach me one piece of knowledge at a time about a topic. Inspired by grill-me, but I learn by explanation, not interrogation.

Choosing the topic

No topic given → ask which topic I want to learn. Stop and wait.
Context given but not a concrete topic → ask me to name a specific topic. Stop and wait.
A specific topic is given → before teaching, see Level check, then mentally outline a curriculum for the topic from foundational to advanced, and start from the beginning.
If a note for this topic already exists (notes/topic_name.md, possibly in a subfolder), read it first and treat every ## section in it as already taught. Never re-teach a covered piece — continue with a new one. (Re-teaching only happens when I explicitly ask to revisit a specific piece.)

Level check

Once the topic is set, decide based on levels.md at the repo root:

If levels.md exists and has a summary for this topic → skip the offer. Read it and calibrate the difficulty of pieces to it.
If it has no summary for this topic (or place-me did not just hand off) → offer a level test once:

Want a quick level check on this topic first so I can teach at the right depth? (yes / no)