Reshape the repo into a src/qcal pip package so real calibration engineers
can drop qcal into their workflow without cloning the HF Space. The existing
Gradio app and decoder stage keep working as-is.
* src/ layout + pyproject.toml with [ml], [decoder], [gui], [all] extras and
a `qcal = qcal.cli:app` console script.
* qcal.fit: scipy.optimize curve fits for Rabi (damped sine), Ramsey (damped
cosine w/ detuning), T1 / T2-echo (exp decay). All return a FitResult
dataclass with R^2; recover synthesized params with R^2≈1.0.
* qcal.data: from_array / from_npy / from_npz adapters. Render matplotlib
plots (line / heatmap / scatter) per experiment type, overlay the fit
curve, and wire numeric summaries + fit summaries into the VLM prompt.
* qcal.analyzer: new analyze_payload() convenience wrapper; AnalysisResult
now carries fit_params, fit, and source, and exposes _repr_markdown_.
* qcal.decoder: _repr_markdown_ on DecoderResult for Jupyter.
* qcal.config: TOML-backed config under…
