Add Phase 1A-C + ICE warehouse stocks: prices, methodology, pipeline automation

Phase 1A — KC=F Coffee Futures Prices:
- New extract/coffee_prices/ package (yfinance): downloads KC=F daily OHLCV,
  stores as gzip CSV with SHA256-based idempotency
- SQLMesh models: raw/coffee_prices → foundation/fct_coffee_prices →
  serving/coffee_prices (with 20d/50d SMA, 52-week high/low, daily return %)
- Dashboard: 4 metric cards + dual-line chart (close, 20d MA, 50d MA)
- API: GET /commodities/<ticker>/prices

Phase 1B — Data Methodology Page:
- New /methodology route with full-page template (base.html)
- 6 anchored sections: USDA PSD, CFTC COT, KC=F price, ICE warehouse stocks,
  data quality model, update schedule table
- "Methodology" link added to marketing footer

Phase 1C — Automated Pipeline:
- supervisor.sh updated: runs extract_cot, extract_prices, extract_ice in
  sequence before transform
- Webhook failure alerting via ALERT_WEBHOOK_URL env var (ntfy/Slack/Telegram)

ICE Warehouse Stocks:
- New extract/ice_stocks/ package (niquests): normalizes ICE Report Center CSV
  to canonical schema, hash-based idempotency, soft-fail on 404 with guidance
- SQLMesh models: raw/ice_warehouse_stocks → foundation/fct_ice_warehouse_stocks
  → serving/ice_warehouse_stocks (30d avg, WoW change, 52w drawdown)
- Dashboard: 4 metric cards + line chart (certified bags + 30d avg)
- API: GET /commodities/<code>/stocks

Foundation:
- dim_commodity: added ticker (KC=F) and ice_stock_report_code (COFFEE-C) columns
- macros/__init__.py: added prices_glob() and ice_stocks_glob()
- pipelines.py: added extract_prices and extract_ice entries

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/materia/pipelines.py

@@ -20,6 +20,14 @@ PIPELINES = {
         "command": ["uv", "run", "--package", "cftc_cot", "extract_cot"],
         "timeout_seconds": 1800,
     },
+    "extract_prices": {
+        "command": ["uv", "run", "--package", "coffee_prices", "extract_prices"],
+        "timeout_seconds": 300,
+    },
+    "extract_ice": {
+        "command": ["uv", "run", "--package", "ice_stocks", "extract_ice"],
+        "timeout_seconds": 600,
+    },
     "transform": {
         "command": ["uv", "run", "--package", "sqlmesh_materia", "sqlmesh", "-p", "transform/sqlmesh_materia", "plan", "prod", "--no-prompts", "--auto-apply"],
         "timeout_seconds": 3600,