feat(deploy): fix docker deployment and add backend i18n

- Docker Deployment Fixes:
  - Switch base images to docker.m.daocloud.io to resolve registry 401 errors
  - Add Postgres and Redis services to docker-compose.traefik.yml
  - Fix frontend build: replace missing icons (Globe->Location, Chart->TrendCharts)
  - Fix frontend build: resolve pnpm CI/TTY issues and frozen lockfile errors
  - Add missing backend dependencies (sqlalchemy, psycopg2, redis-py, celery, docker-py) in pixi.toml
  - Ensure database tables are created on startup (lifespan event)

- Backend Internationalization (i18n):
  - Add backend/app/core/i18n.py for locale handling
  - Update API endpoints (jobs, tasks, uploads, results) to return localized messages
  - Support 'Accept-Language' header (en/zh)

- Documentation:
  - Update DOCKER_DEPLOYMENT.md with new architecture and troubleshooting
  - Update AGENTS.md with latest stack details and deployment steps
  - Update @fix_plan.md status

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

backend/app/models/job.py

@@ -15,6 +15,15 @@ class JobStatus(str, enum.Enum):
     FAILED = "failed"        # 执行失败
 
 
+class StepStatus(str, enum.Enum):
+    """步骤状态"""
+    PENDING = "PENDING"
+    RUNNING = "RUNNING"
+    SUCCESS = "SUCCESS"
+    FAILED = "FAILED"
+    SKIPPED = "SKIPPED"
+
+
 class Job(Base):
     __tablename__ = "jobs"
 
@@ -48,3 +57,36 @@ class Job(Base):
     started_at = Column(DateTime(timezone=True), nullable=True)
     completed_at = Column(DateTime(timezone=True), nullable=True)
     updated_at = Column(DateTime(timezone=True), onupdate=func.now())
+
+
+class Step(Base):
+    """任务步骤"""
+    __tablename__ = "job_steps"
+
+    id = Column(Integer, primary_key=True, index=True)
+    job_id = Column(String, index=True)  # ForeignKey("jobs.id") - simplified for SQLite/No-Relation
+    step_id = Column(String)  # digger, shoter, etc.
+    name = Column(String)
+    status = Column(Enum(StepStatus), default=StepStatus.PENDING)
+
+    start_at = Column(DateTime(timezone=True), nullable=True)
+    end_at = Column(DateTime(timezone=True), nullable=True)
+    duration_ms = Column(Integer, nullable=True)
+
+    summary = Column(Text, nullable=True)
+    error = Column(Text, nullable=True)
+
+
+class JobLog(Base):
+    """任务日志"""
+    __tablename__ = "job_logs"
+
+    id = Column(Integer, primary_key=True, index=True)
+    job_id = Column(String, index=True)
+    step_id = Column(String, nullable=True)
+
+    level = Column(String, default="INFO")
+    message = Column(Text)
+    timestamp = Column(DateTime(timezone=True), server_default=func.now())
+    seq = Column(Integer, default=0)
+