Initial scaffold: Nakama backend, Godot client, content schema

Sets up the Step 1 (Project Foundation) and Step 2 (Content Schemas) scaffold
from the implementation sequence. Includes Docker Compose stack, Nakama
TypeScript module stubs, PostgreSQL migration, Godot 4 project shell with
scene stubs and NakamaClient singleton, YAML content schemas for all entity
types, and example data for 3 characters, 2 jobs, and all 7 core resources.

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

docker-compose.yml

@@ -0,0 +1,75 @@
+services:
+  # Nakama game backend
+  nakama:
+    image: heroiclabs/nakama:3.22.0
+    container_name: xyvera_nakama
+    depends_on:
+      cockroachdb:
+        condition: service_healthy
+    entrypoint:
+      - "/bin/sh"
+      - "-ecx"
+      - >
+        /nakama/nakama migrate up --database.address root@cockroachdb:26257/nakama &&
+        /nakama/nakama
+        --name xyvera
+        --database.address root@cockroachdb:26257/nakama
+        --socket.server_key "${NAKAMA_SERVER_KEY:-xyvera-dev-key}"
+        --session.token_expiry_sec 7200
+        --runtime.path /nakama/data/modules
+        --logger.level DEBUG
+    volumes:
+      - ./nakama/modules:/nakama/data/modules
+      - nakama_data:/nakama/data
+    ports:
+      - "7349:7349"   # client API
+      - "7350:7350"   # gRPC API
+      - "7351:7351"   # console UI
+    environment:
+      NAKAMA_SERVER_KEY: "${NAKAMA_SERVER_KEY:-xyvera-dev-key}"
+    restart: unless-stopped
+
+  # CockroachDB — required by Nakama
+  cockroachdb:
+    image: cockroachdb/cockroach:v23.2.3
+    container_name: xyvera_cockroachdb
+    command: start-single-node --insecure --store=attrs=ssd,path=/var/lib/cockroach/
+    volumes:
+      - cockroach_data:/var/lib/cockroach
+    ports:
+      - "26257:26257"
+      - "8080:8080"   # CockroachDB admin UI
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8080/health?ready=1"]
+      interval: 10s
+      timeout: 5s
+      retries: 10
+      start_period: 30s
+    restart: unless-stopped
+
+  # PostgreSQL — game content, player state, and economy data
+  # Separate from Nakama's CockroachDB so schema migrations are clean and
+  # standalone from the Nakama-managed tables.
+  postgres:
+    image: postgres:16-alpine
+    container_name: xyvera_postgres
+    environment:
+      POSTGRES_DB: xyvera
+      POSTGRES_USER: xyvera
+      POSTGRES_PASSWORD: "${POSTGRES_PASSWORD:-xyvera-dev-pass}"
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+      - ./migrations:/docker-entrypoint-initdb.d:ro
+    ports:
+      - "5432:5432"
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U xyvera -d xyvera"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+    restart: unless-stopped
+
+volumes:
+  nakama_data:
+  cockroach_data:
+  postgres_data: