Initial import: open-design source for helix-mind.ai distribution

This repository contains the open-design daemon CLI source code, built
and packaged at https://helix-mind.ai/cli/open-design/latest.tgz for use
by the HelixMind /design slash command.

Licenses: Apache-2.0 (root) + MIT (skills/*)

apps/web/src/providers/sse.ts

@@ -0,0 +1,38 @@
+export type ParsedSseFrame =
+  | { kind: 'event'; event: string; data: Record<string, unknown>; id?: string }
+  | { kind: 'comment'; comment: string }
+  | { kind: 'empty' };
+
+export function parseSseFrame(frame: string): ParsedSseFrame | null {
+  const lines = frame.split('\n');
+  const comments: string[] = [];
+  let event = 'message';
+  let id: string | undefined;
+  const dataLines: string[] = [];
+
+  for (const rawLine of lines) {
+    const line = rawLine.endsWith('\r') ? rawLine.slice(0, -1) : rawLine;
+    if (line.startsWith(':')) {
+      comments.push(line.slice(1).trimStart());
+    } else if (line.startsWith('event: ')) {
+      event = line.slice(7).trim();
+    } else if (line.startsWith('id: ')) {
+      id = line.slice(4).trim();
+    } else if (line.startsWith('data: ')) {
+      dataLines.push(line.slice(6));
+    }
+  }
+
+  if (dataLines.length === 0) {
+    if (comments.length > 0) {
+      return { kind: 'comment', comment: comments.join('\n') };
+    }
+    return { kind: 'empty' };
+  }
+
+  try {
+    return { kind: 'event', event, data: JSON.parse(dataLines.join('\n')), ...(id ? { id } : {}) };
+  } catch {
+    return null;
+  }
+}