Add Powerwall to leaderboard + 3-way category filter

- Synthesised one hybrid entry (Tesla Powerwall 3, installed price €9500)
  appended to the catalog. Tagged installation: hybrid; LP runs with
  allows_export=True for those.
- Replaced single 'plug-in only' checkbox with three category filters:
  ≤0.8 kW plug-in, ≤2.5 kW plug-in, Hybrid/DC-coupled. Default: all on.
  Filter selection persists in localStorage.
- API now tags every row with a category so the JS can filter without
  re-fetching. SSR rows carry data-category for first-paint filtering.
- Store quote left blank for hybrids since thuisbatterijgids.net only
  models plug-in arithmetic.

Dockerfile

@@ -4,18 +4,25 @@ ENV PYTHONUNBUFFERED=1 \
     PYTHONDONTWRITEBYTECODE=1 \
     PIP_DISABLE_PIP_VERSION_CHECK=1 \
     PIP_NO_CACHE_DIR=1 \
-    PORT=8080
+    PYTHONPATH=/app/src
 
 WORKDIR /app
 
-COPY pyproject.toml uv.lock README.md ./
-COPY src ./src
-
+# Install dependencies only (not the package itself), so the source tree at
+# /app stays the runtime layout the app expects: web.py uses
+# Path(__file__).resolve().parents[2] / "data" / "raw" to find CSVs, which
+# only resolves correctly when the package is imported from /app/src.
+COPY pyproject.toml uv.lock ./
 RUN pip install --no-cache-dir uv \
- && uv pip install --system --no-cache .
+ && uv pip install --system --no-cache \
+      "pandas>=2.2" "scipy>=1.13" "numpy>=2.0" "flask>=3.0" "gunicorn>=21.0"
 
+COPY src ./src
 COPY data ./data
 
 EXPOSE 8080
 
-CMD ["sh", "-c", "gunicorn pluginbattery.web:app --bind 0.0.0.0:${PORT:-8080} --workers 1 --timeout 120"]
+CMD ["gunicorn", "pluginbattery.web:app", \
+     "--bind", "0.0.0.0:8080", \
+     "--workers", "1", \
+     "--timeout", "120"]