build(deps): declare implicit core deps and add optional client group

Move vllm, flwr, autogen-agentchat, transformers, groq, azure-ai-ml
into [tool.poetry.group.clients] so CI can install without CUDA/ML
runtime dependencies:
  poetry install --without clients --with dev

Declare packages used by aiopslab/ core modules that were previously
only available as undeclared transitive dependencies:
  docker    - aiopslab/service/dock.py
  pandas    - aiopslab/orchestrator/actions/base.py, observer/*.py
  pytz      - aiopslab/observer/__init__.py, metric_api.py
  requests  - aiopslab/observer/trace_api.py, service/telemetry/loki.py
  pyyaml    - aiopslab/config.py, generators/fault/*.py, service/*.py
  tiktoken  - aiopslab/orchestrator/evaluators/quantitative.py

Add [tool.poetry.group.dev] with pytest + pytest-asyncio and register
the 'integration' pytest marker for the new smoke test.

Author: srmanda-cs