chore: initial Observable workspace with technical README

docs/data/in-n-out-ca-csv.json.js

@@ -0,0 +1,41 @@
+const csvUrl =
+  "https://raw.githubusercontent.com/madmao/castle-compass/master/csv/In%20N%20Out.csv";
+const response = await fetch(csvUrl);
+if (!response.ok) {
+  throw new Error(`In-N-Out CSV request failed: ${response.status}`);
+}
+
+const rows = (await response.text()).split(/\r?\n/).filter(Boolean);
+
+const stores = rows
+  .map((line, index) => {
+    const [latRaw, lonRaw] = line.split(",");
+    const latitude = Number(latRaw);
+    const longitude = Number(lonRaw);
+
+    if (!Number.isFinite(latitude) || !Number.isFinite(longitude)) return null;
+
+    const inCaliforniaBounds =
+      latitude >= 32 &&
+      latitude <= 42.5 &&
+      longitude >= -125 &&
+      longitude <= -114;
+
+    if (!inCaliforniaBounds) return null;
+
+    return {
+      id: `ino/${index}`,
+      name: "In-N-Out Burger",
+      latitude,
+      longitude,
+    };
+  })
+  .filter(Boolean);
+
+const dedup = new Map();
+for (const store of stores) {
+  const key = `${store.latitude.toFixed(5)},${store.longitude.toFixed(5)}`;
+  if (!dedup.has(key)) dedup.set(key, store);
+}
+
+process.stdout.write(JSON.stringify(Array.from(dedup.values())));