Add makefile

[Joffcom]

Adds a Makefile to check Python version, set up venv and install requirements, Also updates contributing guide to cover the new process.

[netlify]

✅ Deploy Preview for n8n-docs ready!

Name	Link
🔨 Latest commit	334dce3
🔍 Latest deploy log	https://app.netlify.com/sites/n8n-docs/deploys/67c06b164455930008d822fb
😎 Deploy Preview	https://deploy-preview-2917--n8n-docs.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[github-actions]

Summary

Status	Count
🔍 Total	12
✅ Successful	9
⏳ Timeouts	0
🔀 Redirected	0
👻 Excluded	3
❓ Unknown	0
🚫 Errors	0
Full Github Actions output

[github-actions]

Overall readability score: 44.72 (🟢 +0)

File	Readability
README.md	62.52 (🟢 +0)

View detailed metrics

🟢 - Shows an increase in readability
🔴 - Shows a decrease in readability

File	Readability	FRE	GF	ARI	CLI	DCRS
README.md	62.52	51.14	9.25	9.9	11.7	8.05
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

Averages:

	Readability	FRE	GF	ARI	CLI	DCRS
Average	44.72	36.11	11.54	14.54	14.21	8.39
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

View metric targets

Metric	Range	Ideal score
Flesch Reading Ease	100 (very easy read) to 0 (extremely difficult read)	60
Gunning Fog	6 (very easy read) to 17 (extremely difficult read)	8 or less
Auto. Read. Index	6 (very easy read) to 14 (extremely difficult read)	8 or less
Coleman Liau Index	6 (very easy read) to 17 (extremely difficult read)	8 or less
Dale-Chall Readability	4.9 (very easy read) to 9.9 (extremely difficult read)	6.9 or less

[evilnick]

Looks promising - will have to test it out a few places