Add shared library for APIs/chunking

lib/chunk.js

@@ -0,0 +1,32 @@
+const CHUNK_SIZE = 2000;
+const CHUNK_OVERLAP = 200;
+
+export function chunkText(text) {
+    const cleaned = String(text || "").replace(/\r\n/g, "\n").trim();
+    if (!cleaned) return [];
+    if (cleaned.length <= CHUNK_SIZE) return [cleaned];
+
+    const chunks = [];
+    let start = 0;
+
+    while (start < cleaned.length) {
+        let end = Math.min(start + CHUNK_SIZE, cleaned.length);
+
+        if (end < cleaned.length) {
+            const slice = cleaned.slice(start, end);
+            const lastBreak = Math.max(slice.lastIndexOf("\n"), slice.lastIndexOf(" "));
+            if (lastBreak > CHUNK_SIZE * 0.5) {
+                end = start + lastBreak;
+            }
+        }
+
+        const chunk = cleaned.slice(start, end).trim();
+        if (chunk) chunks.push(chunk);
+        if (end >= cleaned.length) break;
+
+        const nextStart = end - CHUNK_OVERLAP;
+        start = nextStart <= start ? end : nextStart;
+    }
+
+    return chunks;
+}