feat: update ctm-token-calculator to use Mercury and notebook deliverables

Replace Streamlit and JupyterLab commands with Mercury for serving interactive
notebooks as web apps. Update README to reflect new architecture where
notebooks are the primary deliverables, utilizing Mercury input widgets for
live client tuning. Add export_report.py script to generate LLM-readable
HTML/Markdown reports from the notebooks. Update corrected business case
notebook to include Mercury dependency and usage instructions.

studies/202512_GenesysCX/ctm-token-calculator/pyproject.toml

@@ -15,8 +15,8 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-app = ["streamlit>=1.30"]
-notebook = ["jupyterlab>=4.0", "ipywidgets>=8.0"]
+app = ["mercury>=3.2"]
+notebook = ["jupyterlab>=4.0", "ipywidgets>=8.0", "nbconvert>=7", "tabulate>=0.9"]
 dev = ["pytest>=7.4", "mypy>=1.8"]
 
 [tool.setuptools.packages.find]