docs: deprecate relaying via Gelato

[Christoph (chrisdotn)]

Relaying transactions through Gelato is unavailable from September 1, 2026.

• Replace the Gelato Relay guide body with a deprecation notice and a migration table pointing to the Safe4337Pack. The page and its two inbound redirects stay live.
• Mark the guide as deprecated in the sidebar and on the Relay Kit landing page.
• Drop Gelato from the SDK overview bullet list and Relay Kit card.
• Replace the Gelato reference in the "Relayer" glossary entry.
• Replace the GelatoRelayPack snippet in llms-ctx.txt and llms-ctx-full.txt with a Safe4337Pack example. The old snippet also used a pre-v2 API that no longer matched the SDK.

The migrate-to-v2 guide keeps its GelatoRelayPack section as a historical migration record.

What it solves

Resolves #

Changelog

Checklist

• I've followed all safe-docs pull request rules

[github-actions]

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Website:
https://docs_deprecate_gelato_relay--docs.review.5afe.dev

[github-actions]

Overall readability score: 36.57 (🟢 +0)

File	Readability
relay-kit.mdx	42.03 (🔴 -5.74)
overview.mdx	45.37 (🔴 -0.02)
gelato-relay.mdx	72.5 (🟢 +5.13)
glossary.md	56.98 (🟢 +0.15)

View detailed metrics

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

File	Readability	FRE	GF	ARI	CLI	DCRS
relay-kit.mdx	42.03	38.32	11.9	14.4	14.32	9.17
	🔴 -5.74	🔴 -14.89	🟢 +0.3	🔴 -0.6	🔴 -1.5	🔴 -0.25
overview.mdx	45.37	40.24	10.83	14.6	15.71	8.1
	🔴 -0.02	🔴 -0.61	🟢 +0	🔴 -0.2	🟢 +0.17	🟢 +0.04
gelato-relay.mdx	72.5	67.96	8.27	9	10.54	7.25
	🟢 +5.13	🟢 +13.54	🟢 +1.29	🟢 +1.3	🔴 -0.04	🔴 -0.36
glossary.md	56.98	39.33	10.17	11.9	12.87	7.26
	🟢 +0.15	🟢 +0	🟢 +0.05	🟢 +0	🟢 +0	🟢 +0.02

Averages:

	Readability	FRE	GF	ARI	CLI	DCRS
Average	36.57	31.41	13.24	16.35	14.76	8.72
	🟢 +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