rename: chapitre/projet templates to chapter/project

Standardize French template names to English across blueprints,
content files, PHP templates, Vue components and Pinia stores.

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

public/site/blueprints/pages/chapter.yml

@@ -0,0 +1,41 @@
+title: Chapitre
+
+tabs:
+  contentTab:
+    label: Contenu
+    columns:
+      main:
+        width: 2/3
+        sections:
+          fields:
+            type: fields
+            fields:
+              blueprint: fields/blueprint
+              text:
+                label: Contenu
+                type: blocks
+                fieldsets:
+                  text:
+                    label: Texte
+                    type: group
+                    fieldsets:
+                      - heading
+                      - text
+                      - list
+                      - quote
+                  media:
+                    label: Medias
+                    type: group
+                    fieldsets:
+                      - map
+                      - image
+                      - video
+      sidebar:
+        width: 1/3
+        sections:
+          maps:
+            label: Cartes
+            type: pages
+            template: map
+
+  files: tabs/files