Add n8n community node, /api/v1/render alias, and job webhooks for OSS automation.

Payment-free self-hosted builds keep full API access with optional webhookUrl callbacks and the published n8n-nodes-songs2vid package source under integrations/n8n.

docs/n8n.md

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+# n8n integration (OSS)
+
+Automate self-hosted Songs2VID with the community package **[`n8n-nodes-songs2vid`](https://www.npmjs.com/package/n8n-nodes-songs2vid)**.
+
+Full hosted guide: [https://docs.songs2vid.com/docs/n8n](https://docs.songs2vid.com/docs/n8n)
+
+## Install
+
+In n8n → **Settings → Community nodes** → install:
+
+```text
+n8n-nodes-songs2vid
+```
+
+Or from this repo for local development:
+
+```bash
+cd integrations/n8n
+npm install
+npm run build
+```
+
+## Auth
+
+1. Dashboard → **Settings → API key** → create `s2yt_live_…`
+2. n8n credential **Songs2VID API**: paste key, Base URL = your instance (e.g. `http://localhost:3000`)
+
+OSS has **no plan gate** — API keys work whenever YouTube is connected.
+
+## Flow
+
+1. **Upload** cover (`type=image`) and audio (`type=audio`)
+2. **Create Render** (`POST /api/v1/render`) with paths + optional `webhookUrl`
+3. Handle completion via n8n **Webhook** or poll `GET /api/v1/jobs/:id`
+
+Package source: [`integrations/n8n`](../integrations/n8n/).