docs: enrich docs/specs and remove placeholders

**Motivations:**
- Make docs/specs implementation-ready without empty sections or placeholders.

**Root causes:**
- Multiple specs still contained non-actionable placeholders (N/A, “see above”, "..."), and inconsistent “no cache” wording.

**Correctifs:**
- Replace placeholders with explicit tables, structures, and typed examples.
- Align “no cache / no memorization” statements where relevant.

**Evolutions:**
- Add a features doc entry to track the documentation enrichment effort.

**Pages affectées:**
- docs/specs/*
- docs/features/docs-specs-enrichment.md
- docs/leo.md
- docs/plan-enrich-docs-specs.md

docs/specs/boutique.md

@@ -211,5 +211,5 @@ function processShop(shop, visitors):
 - **Vidéos** : Time-lapse construction (accéléré).
 - **Animations** : Petit effet de poussière à la pose.
 - **Couleurs** : Bleu (Blueprint).
-- **Textes** : "Construction...".
+- **Textes** : "Construction".
 - **Formes** : Grille de placement.