Migrate Amazon Connect TEI study to the Mercury Notebook Pattern

studies/202602_AmazonConnect -> studies/202602_TEI_Amazon_Connect,
rebuilt as pattern Variant 4 (TEI composite reproduction):

- teicalc/ self-contained engine (stdlib-only): Forrester's tables as
  the never-edited verbatim anchor, NPV/ROI/payback + risk adjustment
  transplanted from core/calculations, ClientDrivers overlay (contacts/
  agents/fixed driver map, growth re-base, identity at composite scale),
  scenario stress with core-identical semantics
- one deliverable notebook (business_case.ipynb): widget-pair sidebar
  drivers, published-vs-overlay KPI columns, cash-flow/waterfall/scenario
  charts, verification gate, backstage JSON data appendix
- gate + tests reproduce the published totals within PDF rounding:
  NPV $78.7M / ROI 342% / payback <6 months (engine $78,713,492 /
  342.48% / 0.7 months); 27 study tests, headless nbconvert green,
  stage simulation leak-free, exports carry the appendix
- old Athena workflow (00_provision..04_export, config.py, seed_data.py)
  deleted; git history preserves it; root test fixture repointed to
  teicalc.anchor
- docs: study README rewritten; root README points new studies at
  template/MercuryNotebook; pattern doc stale ctm-token-calculator paths
  now cite studies/202607_CTM_GenesysCX; Variant 4 cites this study as
  its realized reference

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

studies/202602_TEI_Amazon_Connect/scripts/export_report.py

@@ -0,0 +1,47 @@
+"""Export the deliverable notebooks as LLM-readable report sources.
+
+Executes each notebook fresh (widget defaults — or whatever defaults you edit in),
+then writes both formats to exports/:
+
+  exports/<notebook>.html  — human-reviewable, tables render
+  exports/<notebook>.md    — leanest LLM input
+
+Plotly figures export as JavaScript an LLM cannot read; each notebook's
+machine-readable appendix section carries every number behind them.
+
+Run from the project root:  python scripts/export_report.py [name-filter]
+An optional argument exports only notebooks whose filename contains it.
+"""
+from __future__ import annotations
+
+import subprocess
+import sys
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parent.parent
+NOTEBOOKS = [
+    ROOT / "notebooks" / "business_case.ipynb",
+]
+EXPORTS = ROOT / "exports"
+
+
+def main() -> None:
+    picked = [nb for nb in NOTEBOOKS
+              if len(sys.argv) < 2 or sys.argv[1] in nb.name]
+    if not picked:
+        sys.exit(f"no notebook matches {sys.argv[1]!r}")
+    EXPORTS.mkdir(exist_ok=True)
+    for nb in picked:
+        for fmt in ("html", "markdown"):
+            subprocess.run(
+                [sys.executable, "-m", "nbconvert", "--execute",
+                 "--to", fmt, "--output-dir", str(EXPORTS), str(nb)],
+                check=True, cwd=ROOT,
+            )
+    for p in sorted(EXPORTS.iterdir()):
+        if p.suffix in (".html", ".md"):
+            print(f"wrote {p.relative_to(ROOT)} ({p.stat().st_size / 1024:,.0f} KB)")
+
+
+if __name__ == "__main__":
+    main()