Learn: a /learn/ deep-dive section — markdown lessons as before/after spec progressions

docs/architecture/00-overview.md

@@ -47,6 +47,7 @@ about user-facing widgets. At that overlap, one rule keeps them from drifting:
 | 08  | [vega/editor Techniques](08-vega-editor-techniques.md)          | Reference brief: borrowable Monaco-schema wiring, vega-embed lifecycle, two-tier validation, and data-flow/debounce techniques distilled from the official Vega-Lite editor — plus where we do better.                                                                                                                                                                    |
 | 09  | [Visual Design Language](09-visual-design.md)                   | The _visual_ contract: principles inspired by IBM/Carbon, deliberate divergences (square chrome, free color/theming), the token system (Plex type, 8px spacing, role-based color, motion), component conventions, and where to mine the Carbon/IBM source repos for more. Companion: [`visual-specimen.html`](visual-specimen.html).                                      |
 | 10  | [Interaction & Feedback](10-interaction-and-feedback.md)        | The _interaction_ contract: the feedback-channel decision table, latency/feedback budgets, the non-happy-path triad, the recovery & data-safety contract, the keyboard/focus contract, and the resolved widget patterns (window splitter, toolbar, segmented controls, selectable lists, search, sort, empty states, modals). Cites `spec/` for behavior; owns the _how_. |
+| 11  | [Learning Section](11-learning-section.md)                      | The `/learn/` deep-dive: a marketing-surface Vite entry reusing core + the landing chart embed; markdown-authored lessons (`import.meta.glob`) parsed into an ordered block model; the authoring/engine split (pure parser in core; `marked` only in `src/learn`).                                                                                                        |
 
 ## The non-negotiable layering (every doc assumes this)