[Demo] Instance Monitoring for many self-hosted n8n instances

[konstantintieber]

Description

Demo video: https://www.loom.com/share/ca2f66a2744b4167bfaf1392d84a7198

A sample implementation of this guide: https://www.notion.so/n8n/OEM-Guide-How-to-track-billable-executions-across-instances-35d5b6e0c94f80f4b136c6a32cd67495

How to test:
Follow this readme: https://github.com/n8n-io/n8n-hosting/blob/b6e9f1a56a9827370dc76f478f17eb881e910092/local-cluster/README.md#prerequisites

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Example/configuration update
• CI/CD improvements

Related Issues

Fixes # (issue)
Relates to # (issue)

Screenshots

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Summary by cubic

Adds a local demo that spins up three n8n instances plus an instance-monitoring service that pulls Insights Public API data via token exchange to track billable executions across instances. Supports LIGO-496 by showing the recommended pull-and-store pattern with a simple dashboard.

• New Features
  • Local Kind cluster with three isolated instances (n8n-1..3) via Helm, standalone SQLite, image preload n8nio/n8n:local, and background port-forwards (5678–5680).
  • Token exchange enabled by default: Makefile generates RSA keys and injects trusted key config (N8N_TOKEN_EXCHANGE_*, issuer https://instance-monitoring.local, allowedRoles=["global:admin"]).
  • Instance monitoring service (Node + k8s): mints JWT, exchanges at /rest/auth/oauth/token, calls /api/v1/insights/summary, stores per‑instance daily totals in SQLite PVC, serves a dashboard at /dashboard (localhost:5700). Poll interval via POLL_INTERVAL_SECONDS.
  • Docs and Makefiles for one‑command setup (make up/down), optional .env injection, reduced local resources, and new log helpers: make logs <namespace> and make logs monitoring; sets N8N_INSIGHTS_COMPACTION_INTERVAL_MINUTES=1 for fresher data.

^{Written for commit b6e9f1a. Summary will update on new commits. Review in cubic}