feat(case-study): engineer trial corridor (India, 805 m)

README.md

@@ -50,6 +50,57 @@ See [`docs/tagline/tagline.md`](docs/tagline/tagline.md). Reproduce with
 
 ---
 
+## Web product (P77+) — what the engineer actually clicks
+
+`web/` is a Next.js 16 SPA backed by a FastAPI corridor endpoint on
+the same box. No CLI on the engineer's path.
+
+| | |
+|---|---|
+| **AI input (P81)** | Local Ollama (default `gemma4:e4b`) parses *"ropeway from Shidighat to Bhimashankar plateau, jig-back"* into a structured corridor request. |
+| **Map input (P78)** | Leaflet + OpenStreetMap. Drop two pins, drag to fine-tune. |
+| **Build (P76)** | `POST /api/v1/corridor` → auto-fetches the Copernicus tile (P47) → runs the GA → writes KML / DXF / LandXML / GeoJSON / PNG / PDF / ZIP → job-status URL the SPA polls. |
+| **3-D view (P79)** | Cesium globe, KML loaded as a DataSource, auto-fly to corridor. With `NEXT_PUBLIC_CESIUM_TOKEN` set → Cesium World Terrain + Bing satellite. |
+| **Walkthrough video (P85)** | Client-side `MediaRecorder` on the Cesium canvas + scripted 12-second camera flight → downloadable `.webm`. |
+| **Interactive charts (P80)** | Plotly: elevation profile + cable + supports / GA convergence / per-span tension. |
+| **Refine chat (P86)** | "make it cheaper" / "fewer towers" / "switch to 3S" → Ollama → adjusted `CostWeights` + warm-start → new GA job. |
+| **Permit pack (P82)** | One-button ZIP, plus per-artifact downloads. |
+| **KML alignment (P95)** | Cable shipped at true WGS-84 elevation + 5 m safety buffer so GE-stylised terrain never clips it. `relativeToGround` opt-in available. |
+
+Local dev:
+
+```bash
+source ~/.nvm/nvm.sh && nvm use 20   # Next 16 requires Node ≥ 20
+cd web && npm install && npm run dev # http://localhost:3000
+
+# in another terminal:
+source .venv/bin/activate && ropeway serve   # FastAPI :8000
+
+# and:
+ollama serve   # Ollama for /api/v1/ask + /api/v1/refine
+```
+
+Recovery if Tailwind's native binary mis-installs:
+`rm -rf web/node_modules web/package-lock.json web/.next && cd web && npm install`.
+
+---
+
+## Phase plans
+
+The two planning docs that drive everything else:
+
+* **[`docs/POST_TRIAL_PLAN.md`](docs/POST_TRIAL_PLAN.md)** — the H1/H2/H3 plan
+  written the day of the first engineer trial. H1 + H2 are shipped.
+* **[`docs/POST_TRIAL_PLAN_V2.md`](docs/POST_TRIAL_PLAN_V2.md)** — feedback-loop 1
+  after the trial. Waves A (visualisation correctness, includes the
+  P95 KML fix that just shipped), B (inline document previews —
+  P93), C (UI overhaul — P94), D (full-control editor + manual tower
+  drag + refine v2 + saved projects — P96–P99).
+
+Original phase plan (engine waves P1–P32): [`docs/PHASE_PLAN.md`](docs/PHASE_PLAN.md).
+
+---
+
 ## Quickstart
 
 ```bash

app/streamlit_app.py

@@ -228,6 +228,9 @@ def _load_terrain():
     st.session_state["profile"] = profile
     st.session_state["patch"] = patch
     st.session_state["cfg"] = cfg
+    st.session_state["loaded_label"] = (
+        f"sidebar {mode} corridor ({optimizer_mode})"
+    )
     # Tower-height edits start equal to the optimized layout.
     st.session_state["edited_heights"] = [t.height for t in st.session_state["alignment"].towers]
 
@@ -250,6 +253,10 @@ def _load_terrain():
 eval_res = st.session_state["eval"]
 history_best, history_avg = st.session_state["history"]
 
+# "What is currently loaded" — surfaces in every tab so it's never
+# ambiguous which corridor the Optimize / 3-D / Projects tabs show.
+_loaded_label = st.session_state.get("loaded_label", "default synthetic 3 km corridor")
+
 
 # ---- Tab 0: Demo (civil-engineer-friendly entry point) ----
 with tab_demo:
@@ -277,6 +284,10 @@ def _load_terrain():
         "Roosevelt Island Tramway (NYC) — urban jig-back":
             dict(start=(-73.9580, 40.7570), end=(-73.9495, 40.7610),
                  system="jigback", note="Queensboro Bridge fly-over."),
+        "Bhimashankar pilgrim ropeway (India) — Jyotirlinga, 2.18 km":
+            dict(start=(73.5123812, 19.0691450), end=(73.5330820, 19.0700494),
+                 system="jigback",
+                 note="2026-05-25 engineer trial. Western Ghats pilgrim line, Shidighat → Bhimashankar plateau. 742 m terminal rise over 2.18 km (34 % slope). Jig-back, single intermediate tower."),
         "Mexico City L2 + Caracas (new) — try a corridor":
             dict(start=(-99.04, 19.34), end=(-99.00, 19.37),
                  system="mgd", note="Click two map points to override."),
@@ -404,6 +415,7 @@ def _load_terrain():
         st.session_state["alignment"] = align
         st.session_state["eval"] = eval_res_demo
         st.session_state["history"] = (result.history_best, result.history_avg)
+        st.session_state["loaded_label"] = f"{preset_name} (system: {demo_system})"
 
         progress.progress(1.0, text="Done.")
 
@@ -427,14 +439,81 @@ def _load_terrain():
             fig_c, _ = plot_convergence(result.history_best, result.history_avg)
             st.pyplot(fig_c, width="stretch")
 
+        # ---- P74: one-button "build me everything" ZIP ----
+        st.markdown("---")
+        st.markdown("### Download the permit pack")
+        st.caption(
+            "Single ZIP with KML (Google Earth), DXF (AutoCAD), LandXML, "
+            "GeoJSON (QGIS), BoM, capex estimate, tower schedule, "
+            "convergence + alignment PNGs."
+        )
+
+        import io as _io
+        import zipfile
+        from datetime import datetime as _dt
+        from ropeway.bom import build_bom as _build_bom
+        from ropeway.cost import Region as _Region, estimate_cost as _est_cost
+        from ropeway.dxf_export import alignment_to_dxf as _to_dxf
+        from ropeway.io import (
+            alignment_to_csv as _to_csv,
+            alignment_to_geojson as _to_geojson,
+            alignment_to_kml as _to_kml,
+        )
+        from ropeway.landxml import alignment_to_landxml as _to_landxml
+        from ropeway.multi_rope import RopewaySystemType as _RST
+
+        slug = "".join(c if c.isalnum() else "_" for c in preset_name).strip("_").lower()
+        with _io.BytesIO() as buf:
+            with zipfile.ZipFile(buf, "w", zipfile.ZIP_DEFLATED) as zf:
+                import tempfile as _tmp
+                with _tmp.TemporaryDirectory() as td:
+                    td_p = Path(td)
+                    _to_kml(align, profile, td_p / "alignment.kml",
+                            project_name=preset_name, segments=eval_res_demo.segments)
+                    _to_dxf(align, profile, td_p / "alignment.dxf",
+                            project_name=preset_name)
+                    _to_landxml(align, profile, td_p / "alignment.landxml")
+                    _to_geojson(align, profile, td_p / "alignment.geojson")
+                    _to_csv(align, profile, td_p / "towers.csv")
+
+                    sys_enum_map = {"jigback": _RST.JIG_BACK, "mgd": _RST.MGD,
+                                    "bgd": _RST.BGD, "3s": _RST.TGD_3S,
+                                    "chair": _RST.CHAIRLIFT, "funitel": _RST.FUNITEL}
+                    bom_obj = _build_bom(align, project_name=preset_name,
+                                         system=sys_enum_map[demo_system], cfg=cfg_demo)
+                    (td_p / "bom.csv").write_text(bom_obj.as_csv())
+                    est_obj = _est_cost(bom_obj, region=_Region.EMERGING)
+                    (td_p / "cost_estimate.csv").write_text(est_obj.as_csv())
+
+                    fig_a.savefig(td_p / "alignment.png", dpi=140)
+                    fig_c.savefig(td_p / "convergence.png", dpi=140)
+
+                    for f in sorted(td_p.iterdir()):
+                        zf.write(f, arcname=f"{slug}/{f.name}")
+
+            zip_bytes = buf.getvalue()
+
+        stamp = _dt.utcnow().strftime("%Y%m%d_%H%M")
+        st.download_button(
+            label="⬇ Download permit pack (ZIP)",
+            data=zip_bytes,
+            file_name=f"ropeway_{slug}_{stamp}.zip",
+            mime="application/zip",
+            type="primary",
+            use_container_width=True,
+            key="demo_zip_download",
+        )
+
         st.caption(
-            "Open the **3-D Digital Twin** tab above for the interactive view, "
-            "or the **Optimize** tab for downloads (DXF, LandXML, PDF, BoM, GeoJSON)."
+            "Need the interactive 3-D viewer? Open the **3-D Digital Twin** tab. "
+            "Need a knob-tunable run? **Advanced** users open the sidebar — but the "
+            "sidebar `Run optimization` button **overwrites** this Demo result."
         )
 
 
 # ---- Tab 1: Optimize ----
 with tab_opt:
+    st.caption(f"Currently loaded: **{_loaded_label}**")
     rep = eval_res.report
     n_int = max(0, len(alignment.towers) - 2)
     pphpd = _pphpd(float(line_speed), float(cfg.seat_spacing_m),
@@ -487,6 +566,7 @@ def _load_terrain():
 
 # ---- Tab 2: 3-D Digital Twin ----
 with tab_3d:
+    st.caption(f"Currently loaded: **{_loaded_label}**")
     try:
         from stpyvista import stpyvista
         _HAVE_STPYVISTA = True