refactor: unify docker deployment and restructure frontend architecture

This commit implements a unified Docker deployment strategy, moving from separate frontend and backend images to a single, multi-stage build image containing both services. It also introduces a major reorganization of the frontend directory structure and simplifies the environment configuration.

Key changes:
- **Deployment**: Added a multi-stage `Dockerfile` and `docker-entrypoint.sh` to package the Go backend and Nginx-served frontend into a single container.
- **CI/CD**: Updated GitHub Actions workflows (`ci-cd.yml`, `release.yml`) to build and push the new unified image instead of separate ones.
- **Frontend Refactor**: Reorganized `frontend/src/pages` into a domain-driven directory structure (e.g., `auth/`, `admin/`, `content/`, `communication/`, `productivity/`, `settings/`, `misc/`).
- **Configuration**: Simplified `.env.example` and updated `docker-compose.yml` to reflect the unified service model and single host port.
- **Cleanup**: Removed deprecated `docker-compose.demo.yml`, `docker-compose.prod.yml`, and various unused frontend components and services.
- **Backend**: Refactored configuration loading to use exported `GetDurationEnv` for better consistency.

docker-compose.yml

@@ -1,14 +1,16 @@
+icon: https://github.com/Dvorinka/Trackeep/raw/main/trackeepfavi_bg.png
+
 services:
   postgres:
     image: postgres:15-alpine
     environment:
       POSTGRES_DB: ${DB_NAME:-trackeep}
       POSTGRES_USER: ${DB_USER:-trackeep}
-      POSTGRES_PASSWORD: ${DB_PASSWORD:?DB_PASSWORD is required}
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
     ports:
       - "${DB_HOST_PORT:-5433}:5432"
     volumes:
-      - postgres_data:/var/lib/postgres/data
+      - postgres_data:/var/lib/postgresql/data
     restart: unless-stopped
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U ${DB_USER:-trackeep} -d ${DB_NAME:-trackeep}"]
@@ -19,7 +21,6 @@ services:
 
   dragonfly:
     image: ghcr.io/dragonflydb/dragonfly:latest
-    container_name: dragonfly
     ports:
       - "${DRAGONFLY_HOST_PORT:-6380}:6379"
     volumes:
@@ -35,64 +36,29 @@ services:
       retries: 5
       start_period: 30s
 
-  trackeep-backend:
+  trackeep:
     build:
-      context: ./backend
+      context: .
       dockerfile: Dockerfile
     ports:
-      - "${BACKEND_HOST_PORT:-9000}:${BACKEND_PORT:-8080}"
+      - "${HOST_PORT:-8080}:8080"
     env_file:
       - .env
     environment:
-      - APP_VERSION=${APP_VERSION:-1.0.0}
-      - BACKEND_PORT=${BACKEND_PORT:-8080}
-      - FRONTEND_PORT=${FRONTEND_PORT:-3000}
-      - DRAGONFLY_ADDR=${DRAGONFLY_ADDR:-dragonfly:6379}
-      - DRAGONFLY_PASSWORD=${DRAGONFLY_PASSWORD}
-      - VITE_DEMO_MODE=${VITE_DEMO_MODE:-false}
+      - BACKEND_PORT=8080
+      - DB_HOST=postgres
+      - DB_PORT=5432
+      - DRAGONFLY_ADDR=dragonfly:6379
+      - GIN_MODE=release
     volumes:
-      - ./data:/data
       - ./uploads:/app/uploads
-      - /var/run/docker.sock:/var/run/docker.sock  # Docker socket for updates
+      - ./data:/data
     restart: unless-stopped
     depends_on:
       postgres:
         condition: service_healthy
       dragonfly:
         condition: service_healthy
-    healthcheck:
-      test: ["CMD-SHELL", "wget --no-verbose --tries=1 --spider http://localhost:${BACKEND_PORT:-8080}/health || wget --no-verbose --tries=1 --spider http://localhost:${BACKEND_PORT:-8080}/live"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 40s
-
-  trackeep-frontend:
-    build:
-      context: .
-      dockerfile: ./frontend/Dockerfile
-      args:
-        - VITE_DEMO_MODE=${VITE_DEMO_MODE:-false}
-        - VITE_API_URL=${VITE_API_URL:-http://localhost:${BACKEND_HOST_PORT:-9000}}
-    ports:
-      - "${FRONTEND_HOST_PORT:-3900}:${FRONTEND_PORT:-3000}"
-    environment:
-      - VITE_APP_VERSION=${APP_VERSION:-1.0.0}
-      - VITE_DEMO_MODE=${VITE_DEMO_MODE:-false}
-      - VITE_API_URL=${VITE_API_URL:-http://localhost:${BACKEND_HOST_PORT:-9000}}
-      - FRONTEND_PORT=${FRONTEND_PORT:-3000}
-    volumes:
-      - /var/run/docker.sock:/var/run/docker.sock  # Docker socket for updates
-    depends_on:
-      trackeep-backend:
-        condition: service_healthy
-    restart: unless-stopped
-    healthcheck:
-      test: ["CMD-SHELL", "pgrep nginx > /dev/null || exit 1"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 20s
 
 volumes:
   postgres_data: