Add job creation with UUID, STL upload/library, search, job log, TZ, and CLAUDE.md

- PrintJob: job_uuid (UUID4), customer, logs relationship
- JobLog model + migration 0004 (also includes job_logs table)
- POST /jobs: upload STL or select from library, auto-logs 'Job created'
- GET /jobs?q=: search by customer or filename across all statuses
- app/stl.py: STL_UPLOAD_DIR helper (from env, default /data/stl)
- docker-compose: named volume stl_files mounted at /data/stl
- .env.install: added STL_UPLOAD_DIR and TZ=Europe/Berlin
- CLAUDE.md: full project context for future sessions

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

app/models/print_job.py

@@ -1,4 +1,5 @@
 import enum
+import uuid as _uuid
 from datetime import datetime
 from decimal import Decimal
 
@@ -20,9 +21,11 @@ class PrintJob(Base):
     __tablename__ = "print_jobs"
 
     id: Mapped[int] = mapped_column(primary_key=True)
+    job_uuid: Mapped[str | None] = mapped_column(String(36), unique=True, default=lambda: str(_uuid.uuid4()))
     printer_id: Mapped[int] = mapped_column(ForeignKey("printers.id"))
     filament_id: Mapped[int | None] = mapped_column(ForeignKey("filaments.id"))
     name: Mapped[str] = mapped_column(String(200))
+    customer: Mapped[str | None] = mapped_column(String(200))
     file_name: Mapped[str | None] = mapped_column(String(255))
     status: Mapped[JobStatus] = mapped_column(Enum(JobStatus), default=JobStatus.queued)
     queue_position: Mapped[int | None] = mapped_column(Integer)
@@ -39,3 +42,6 @@ class PrintJob(Base):
 
     printer: Mapped["Printer"] = relationship(back_populates="jobs")
     filament: Mapped["Filament | None"] = relationship(back_populates="jobs")
+    logs: Mapped[list["JobLog"]] = relationship(
+        back_populates="job", order_by="JobLog.created_at.desc()"
+    )