feat: implémentation complète du système Célestopol 1922 pour FoundryVTT v13

- DataModels (character, npc, anomaly, aspect, attribute, equipment)
- ApplicationV2 sheets (character 5 tabs, npc 3 tabs, 4 item sheets)
- DialogV2 pour les jets de dés avec phase de lune
- Templates Handlebars complets (fiches PJ/PNJ, items, jet, chat)
- Styles LESS → CSS compilé (thème vert foncé / orange CopaseticNF)
- i18n fr.json complet (clés CELESTOPOL.*)
- Point d'entrée fvtt-celestopol.mjs avec hooks init/ready
- Assets : polices CopaseticNF, images UI, icônes items
- Mise à jour copilot-instructions.md avec l'architecture réelle

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

system.json

@@ -0,0 +1,74 @@
+{
+  "id": "fvtt-celestopol",
+  "title": "Célestopol 1922",
+  "description": "Système FoundryVTT pour Célestopol 1922, le jeu de rôle d'Antre Monde Éditions.",
+  "manifest": "https://www.uberwald.me/gitea/uberwald/fvtt-celestopol/releases/download/latest/system.json",
+  "download": "#{DOWNLOAD}#",
+  "url": "https://www.uberwald.me/gitea/public/fvtt-celestopol",
+  "license": "LICENSE",
+  "version": "13.0.0",
+  "authors": [
+    {
+      "name": "Uberwald",
+      "discord": "LeRatierBretonnien"
+    }
+  ],
+  "flags": {
+    "hotReload": {
+      "extensions": ["css", "html", "hbs", "json"],
+      "paths": ["css/", "templates/", "lang/fr.json"]
+    }
+  },
+  "compatibility": {
+    "minimum": "13",
+    "verified": "13"
+  },
+  "esmodules": ["fvtt-celestopol.mjs"],
+  "styles": ["css/fvtt-celestopol.css"],
+  "languages": [
+    {
+      "lang": "fr",
+      "name": "Français",
+      "path": "lang/fr.json"
+    }
+  ],
+  "documentTypes": {
+    "Actor": {
+      "character": {
+        "htmlFields": ["description", "notes"]
+      },
+      "npc": {
+        "htmlFields": ["description", "notes"]
+      }
+    },
+    "Item": {
+      "anomaly": { "htmlFields": ["description", "technique", "narratif", "notes"] },
+      "aspect":  { "htmlFields": ["description", "technique", "narratif", "notes"] },
+      "attribute": { "htmlFields": ["description", "technique", "narratif", "notes"] },
+      "equipment": { "htmlFields": ["description", "notes"] }
+    }
+  },
+  "packs": [
+    {
+      "name": "aspects",
+      "label": "Célestopol 1922 — Aspects",
+      "system": "fvtt-celestopol",
+      "path": "packs-system/aspects",
+      "type": "Item"
+    },
+    {
+      "name": "anomalies",
+      "label": "Célestopol 1922 — Anomalies",
+      "system": "fvtt-celestopol",
+      "path": "packs-system/anomalies",
+      "type": "Item"
+    }
+  ],
+  "grid": {
+    "distance": 5,
+    "units": "m"
+  },
+  "primaryTokenAttribute": "resource",
+  "socket": true,
+  "background": "systems/fvtt-celestopol/assets/ui/celestopol_background.webp"
+}