fix: align content field names with blueprints, fix API field calls

Content .txt files:
- narrative.txt (×4): Introduction → Intro
- chapter.txt (×3): Text → Body
- geoformat.txt: Intro → Text
- map.txt: move Text content into Intro field

narrative.json.php:
- parseChapter: $chapter->text() → $chapter->body()
- parseMarker: $marker->text() → $marker->body()
- parseMap: $map->text() → $map->intro()
- narrative root: $page->introduction() → $page->intro()

Also commits Kirby content directory rename (1_cohesion-des-mondes → cohesion-des-mondes)
and new _drafts content.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/content/cohesion-des-mondes/3_e-62/narrative.txt

@@ -0,0 +1,17 @@
+Title: E- 62
+
+----
+
+Author: zahaf inès
+
+----
+
+Cover: - file://otx1ld681oomof2f
+
+----
+
+Intro:<p>Dans la division Papillon, les habitants et leurs identités vivent librement. Enfin, assez librement en comparaison à d'autres divisions comme l'Ancienne Capitale. Mais le Dieu de la rébellion est en chemin.</p>
+
+----
+
+Uuid: 62dxynihkydhmoqk