wedge(002/T103): web Dockerfile + M2MW_STATIC_DIR (site-packages path fix); merge T101/T102

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

.specify/feature.json

@@ -1 +1 @@
-{"feature_directory":"specs/001-market-first-wedge"}
+{"feature_directory":"specs/002-market-web"}

web/Dockerfile

@@ -0,0 +1,24 @@
+# m2-market-web — FastAPI proxy + React SPA in one container (specs/002-market-web).
+# Build context: repo root (needs web/backend + web/frontend).
+
+FROM node:20-slim AS frontend
+WORKDIR /fe
+COPY web/frontend/package.json web/frontend/package-lock.json* ./
+RUN npm install --no-audit --no-fund
+COPY web/frontend/ ./
+RUN npm run build
+
+FROM python:3.12-slim
+WORKDIR /app
+COPY web/backend/pyproject.toml ./backend/pyproject.toml
+COPY web/backend/src ./backend/src
+RUN pip install --no-cache-dir ./backend
+COPY --from=frontend /fe/dist ./frontend/dist
+ENV M2MW_STATIC_DIR=/app/frontend/dist
+
+RUN groupadd --system web && useradd --system --gid web web
+USER web
+EXPOSE 8000
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+    CMD python -c "import urllib.request; urllib.request.urlopen('http://127.0.0.1:8000/health', timeout=2)" || exit 1
+CMD ["uvicorn", "m2_market_web.main:app", "--host", "0.0.0.0", "--port", "8000"]

web/backend/src/m2_market_web/main.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import os
 from pathlib import Path
 
 from fastapi import FastAPI, Request
@@ -19,7 +20,14 @@ def create_app() -> FastAPI:
     def health() -> dict[str, str]:
         return {"status": "healthy"}
 
-    dist = Path(__file__).resolve().parents[3] / "frontend" / "dist"
+    # In the container the package is pip-installed (site-packages), so the
+    # repo-relative parents[3] fallback misses — M2MW_STATIC_DIR wins.
+    dist = Path(
+        os.environ.get(
+            "M2MW_STATIC_DIR",
+            Path(__file__).resolve().parents[3] / "frontend" / "dist",
+        )
+    )
 
     @app.get("/{path:path}", include_in_schema=False)
     def static_or_spa(path: str, request: Request):