seo: optimize Marketplace listing per advisor audit

[sairenchristianbuerano]

• name: Trustabl -> Trustabl - Fix agent reliability issues (headline + URL slug)
• description: lead with the outcome and the full SDK list
• README: drop the banner, rename the heading, rewrite the opening
• update the Marketplace badge to the new slug

[github-actions]

Trustabl scan

trustabl/trustabl-action · seo/marketplace-optimization · 1 findings

Readiness goes from 100 → 100 (+0)

Readiness now   🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩   100 / 100

Projected if all findings resolved   🟩🟩🟩🟩🟩🟩🟩🟩🟩🟩   100 / 100   +0

Findings by severity

Severity	Count
critical	0	▱▱▱▱▱▱▱▱
high	0	▱▱▱▱▱▱▱▱
medium	0	▱▱▱▱▱▱▱▱
low	0	▱▱▱▱▱▱▱▱
info	1	▰▰▰▰▰▰▰▰

Projected headroom — estimate, not a re-scan

Fix scope	Readiness	Δ
Fix critical	100 → 100	+0
+ high	100 → 100	+0
+ medium	100 → 100	+0
+ low	100 → 100	+0
+ info (all)	100 → 100	+0

Projected by re-applying trustabl's own scoring with the listed findings resolved (nothing new introduced). Treat as guidance, not a guarantee.

Metric	Value
Repository	trustabl/trustabl-action
Branch	seo/marketplace-optimization
Readiness score	100
Risk score	0
Findings	1
Max severity	info
Native exit	0
Rules version	4f9d9ce436ca1cd39a2216f63a7cd7dcfc54e0a2

✅ Passed scanning