Add 5 pi extensions: pi-subagents, pi-crew, rpiv-pi, pi-interactive-shell, pi-intercom

extensions/pi-intercom/broker/framing.ts

@@ -0,0 +1,57 @@
+import type { Socket } from "net";
+
+/**
+ * Write a length-prefixed message to a socket.
+ * Format: 4-byte big-endian length + JSON payload
+ */
+export function writeMessage(socket: Socket, msg: unknown): void {
+  const json = JSON.stringify(msg);
+  const payload = Buffer.from(json, "utf-8");
+  const header = Buffer.alloc(4);
+  header.writeUInt32BE(payload.length, 0);
+  socket.write(Buffer.concat([header, payload]));
+}
+
+/**
+ * Create a message reader that handles partial reads.
+ * Calls onMessage for each complete message received.
+ * Protocol or handler errors are reported to onError so the caller can close the socket.
+ */
+export function createMessageReader(
+  onMessage: (msg: unknown) => void,
+  onError: (error: Error) => void,
+) {
+  let buffer = Buffer.alloc(0);
+
+  return (data: Buffer) => {
+    buffer = Buffer.concat([buffer, data]);
+
+    while (buffer.length >= 4) {
+      const length = buffer.readUInt32BE(0);
+      
+      if (buffer.length < 4 + length) {
+        break;
+      }
+
+      const payload = buffer.subarray(4, 4 + length);
+      buffer = buffer.subarray(4 + length);
+
+      let msg: unknown;
+      try {
+        msg = JSON.parse(payload.toString("utf-8"));
+      } catch (error) {
+        const message = error instanceof Error ? error.message : String(error);
+        onError(new Error(`Failed to parse intercom message: ${message}`, { cause: error }));
+        return;
+      }
+
+      try {
+        onMessage(msg);
+      } catch (error) {
+        const message = error instanceof Error ? error.message : String(error);
+        onError(new Error(`Failed to handle intercom message: ${message}`, { cause: error }));
+        return;
+      }
+    }
+  };
+}