docs: qualify failed purchases and saved revocation

[bitcoinuniverseadmin]

A reported error or timeout does not prove a marketplace payment was rejected, and a connection-list error does not prove permissions were removed. The previous guide also described fields that the current connection card does not display.

This change:

• Replaces the unconditional “Failed means no funds or fee” claim with evidence-based recovery guidance: retain the existing marketplace execution/request reference, check that purchase's recorded status, and avoid a replacement purchase or clearing wallet storage while the outcome is uncertain.
• Requires saved revocation acknowledgement and a successful connection-list readback. Explains that read errors are not an empty permission list and write failures do not confirm revocation; existing signed marketplace offers remain usable.
• Matches connection identification to the current card's origin, chain, signature status, saved connection state and expiry, and regenerates the matching llms.txt entry.

Verified against the current wallet HistoryScreen, ConnectedSitesScreen and durable permission service. This is limited to two public documentation pages and their generated index entry; it does not claim new recovery UI or deployed marketplace availability.

Validation: npm test, npm run build (81 pages, internal links and CSP checks), and git diff --check pass. Exact-head GitHub CI is required before merge. No runtime code, retained historical branches, or release artifacts changed.