Hub-and-Spoke Umbau: Multi-Tenant Zentrale + Satellite-Agent

- Backend: Customer/Satellite Models, customer_id auf Server/Job/Audit
- Satellite-API: heartbeat, poll (atomares Claiming), logs, result,
  scan-result, health-report - Auth via X-Api-Key (SHA-256 gehasht)
- Job-Queue: pending/claimed/running/success/failed + Stale-Janitor
- Batch-Trigger: ein Job pro Server, Satellite arbeitet sequenziell ab
- Credentials bleiben lokal: nur symbolische credential_ref zentral
- Neues Paket satellite/: Pull-Loop, WinRM/SSH/CAU/Scanner, PyInstaller-tauglich
- Frontend: Kunden-Switcher, Satelliten-View, Polling statt WebSocket
- Entfernt: WebSocket/Socket.io, Redis, zentrale Credentials, JobRunner
- Docs: README/AGENTS/PROMPT auf neue Architektur aktualisiert

backend/app/models/update_job.py

@@ -1,4 +1,10 @@
-"""Update job + streamed log line models."""
+"""Update job + log line models.
+
+Job lifecycle (pull model):
+  pending -> claimed (satellite picked it up) -> running -> success | failed | cancelled
+A claimed/running job whose satellite goes silent past the stale timeout
+is marked failed by the janitor.
+"""
 
 import enum
 from datetime import UTC, datetime
@@ -9,36 +15,58 @@ from sqlalchemy.orm import Mapped, mapped_column, relationship
 from app.core.database import Base
 
 
-class JobStatus(str, enum.Enum):
+class JobStatus(enum.StrEnum):
     PENDING = "pending"
+    CLAIMED = "claimed"
     RUNNING = "running"
     SUCCESS = "success"
     FAILED = "failed"
     CANCELLED = "cancelled"
 
 
-class JobType(str, enum.Enum):
+class JobType(enum.StrEnum):
     WINDOWS_UPDATE = "windows_update"
     LINUX_UPDATE = "linux_update"
     CAU_RUN = "cau_run"
     HEALTH_CHECK = "health_check"
+    NETWORK_SCAN = "network_scan"
 
 
 class UpdateJob(Base):
     __tablename__ = "update_jobs"
 
     id: Mapped[int] = mapped_column(primary_key=True)
-    server_id: Mapped[int] = mapped_column(ForeignKey("servers.id"), index=True)
-    server: Mapped["Server"] = relationship(back_populates="jobs", lazy="selectin")  # noqa: F821
+
+    customer_id: Mapped[int] = mapped_column(
+        ForeignKey("customers.id"), index=True
+    )
+    customer: Mapped["Customer"] = relationship(back_populates="jobs", lazy="selectin")  # noqa: F821
+
+    # Null for NETWORK_SCAN jobs (target = whole local network)
+    server_id: Mapped[int | None] = mapped_column(
+        ForeignKey("servers.id"), nullable=True, index=True
+    )
+    server: Mapped["Server | None"] = relationship(back_populates="jobs", lazy="selectin")  # noqa: F821
+
+    # Set when a satellite claims the job
+    satellite_id: Mapped[int | None] = mapped_column(
+        ForeignKey("satellites.id"), nullable=True, index=True
+    )
+    satellite: Mapped["Satellite | None"] = relationship(back_populates="jobs", lazy="selectin")  # noqa: F821
 
     type: Mapped[JobType] = mapped_column(Enum(JobType))
     status: Mapped[JobStatus] = mapped_column(Enum(JobStatus), default=JobStatus.PENDING, index=True)
     progress_percent: Mapped[int] = mapped_column(Integer, default=0)
     current_phase: Mapped[str | None] = mapped_column(String(255), nullable=True)
 
-    started_by: Mapped[str] = mapped_column(String(255))  # username
+    # Optional job parameters (e.g. reboot_if_required, scan_subnet)
+    params: Mapped[str | None] = mapped_column(Text, nullable=True)  # JSON blob
+
+    created_by: Mapped[str] = mapped_column(String(255))  # dashboard username
+    claimed_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
     started_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
     finished_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    last_report_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
     error: Mapped[str | None] = mapped_column(Text, nullable=True)
 
     created_at: Mapped[datetime] = mapped_column(