Add the giant/workflow b2luigi task graph (gitea #83)

One workflow TOML now parameterises a whole experiment and `giant workflow
run <spec.toml>` turns it into a b2luigi DAG whose targets are files on
/ceph: nothing already produced is recomputed, every step waits for its
inputs, and HTCondor submission/polling is b2luigi's job.

- spec.py: workflow TOML -> frozen dataclasses with name-uniqueness and
  cross-reference validation, unknown keys rejected the way giant.config
  rejects them, and a short spec_hash per task that folds in its transitive
  parents — so an edited spec re-runs exactly the affected subtree.
- htcondor.py: the CPU/GPU submit settings. The GPU requirement strings
  (ProvidesEtpCeph + optional device/memory pins) are ported from the
  condor-gpu-train-rollout branch rather than rewritten.
- tasks.py: DatasetTask, WarmCacheTask, GeometryOracleTask, TrainEpochTask
  (one short GPU job per epoch, chained via --resume, which the training
  loop already supports unchanged), TrainTask (publishes best.pt/last.pt and
  a concatenated metrics.csv so downstream never sees the epoch fan-out),
  RolloutTask, AnalysisPrepTask, AnalysisComputeTask (one job per plot x
  chunk, walltime sized from run_meta.json at submit time), AnalysisRenderTask
  (always local — the only step importing plotstyle/LaTeX), WorkflowTask.
  Task bodies call the existing entry points; none of them reimplement
  anything.
- run.py + `giant workflow run`: settings wiring and the script b2luigi
  re-executes on workers. add_filename_to_cmd is off because b2luigi passes
  only the script's basename, and --spec is forwarded via
  task_cmd_additional_args so a worker resolves the identical task graph.

configs/workflow_example.toml is the documented starting point.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

pyproject.toml

@@ -108,3 +108,12 @@ explicit = true
 name = "larsbogner"
 url = "https://git.larsbogner.de/api/packages/lars/pypi/simple/"
 explicit = true
+
+# luigi builds task constructors from class-level Parameter descriptors, so a
+# static checker sees no keyword parameters at all on `Task(name=..., ...)`.
+# The workflow code is written against that API; nothing else in the repo is.
+[[tool.ty.overrides]]
+include = ["giant/workflow/**", "tests/test_workflow_tasks.py"]
+
+[tool.ty.overrides.rules]
+unknown-argument = "ignore"