Initial commit: CRDC Arrests API demo app

React + Vite static site demonstrating the CRDC School Arrest Rate API.
Features 6 interactive charts comparing observed arrest data against Bayesian
model estimates across U.S. school districts, with Civilytics visual identity.

- State selector and district search with 'interesting' suggestions (top arrests)
- Animated histogram loading grid showing posterior draw progress
- Charts: time series, rate by group, district vs national, model comparison quadrants, density proxy, exceedance probability
- Static JSON fixture for national rates (no API changes needed)
- Dockerfile + docker-compose.yml for self-hosted deployment
- GitHub Actions workflow and _config.yml for Git Pages

src/data/national_rates.json

@@ -0,0 +1,44 @@
+{
+  "metadata": {
+    "source": "CRDC School Arrest Rate API / Knowles & Miller 2025, White Paper §3 Data",
+    "year": "21-22",
+    "description": "National arrest rates per 1,000 students for each race×sex group in the 2021-22 CRDC. Generated from crdc_2122 with RACE != TOTAL and SEX != TOTAL: sum(ARRESTS) / (sum(stu_enroll)/1000).",
+    "note": "These are observed national rates, used for comparison in Charts 3 & 6."
+  },
+  "rates_per_1000": {
+    "WH_F": 0.34,
+    "WH_M": 0.67,
+    "BL_F": 1.25,
+    "BL_M": 1.98,
+    "HI_F": 0.42,
+    "HI_M": 0.88,
+    "AM_F": 0.91,
+    "AM_M": 1.40
+  },
+  "observed_arrests": {
+    "WH_F": 3653,
+    "WH_M": 7606,
+    "BL_F": 4420,
+    "BL_M": 7246,
+    "HI_F": 2876,
+    "HI_M": 6270,
+    "AM_F": 202,
+    "AM_M": 327
+  },
+  "enrollment": {
+    "WH_F": 10624313,
+    "WH_M": 11322741,
+    "BL_F": 3530162,
+    "BL_M": 3667523,
+    "HI_F": 6805008,
+    "HI_M": 7109091,
+    "AM_F": 222963,
+    "AM_M": 233442
+  },
+  "totals": {
+    "arrests": 34846,
+    "enrollment": 48596489,
+    "rate_per_1000": 0.72,
+    "districts_reporting_arrests_pct": 11.6
+  }
+}