feat: Add project foundation, documentation, and Docker setup

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docker-compose.yml

@@ -0,0 +1,40 @@
+version: '3.8'
+
+services:
+  postgres:
+    image: postgres:15-alpine
+    container_name: training-tracker-db
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+      POSTGRES_DB: training_tracker
+    ports:
+      - "5432:5432"
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U postgres"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  backend:
+    build:
+      context: ./backend
+      dockerfile: Dockerfile.dev
+    container_name: training-tracker-backend
+    environment:
+      DB_HOST: postgres
+      DB_PORT: 5432
+      DB_USER: postgres
+      DB_PASSWORD: postgres
+      DB_NAME: training_tracker
+      PORT: 8080
+    ports:
+      - "8080:8080"
+    depends_on:
+      postgres:
+        condition: service_healthy
+
+volumes:
+  postgres_data: