Show cached data in account detail view when server is not reachable

[daniele-verducci]

Fix #15236

🖼️ Screenshots

🏚️ Before	🏡 After

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not needed
• 🔙 Backport requests are created or not needed: /backport to stable-xx.x
• 📅 Milestone is set
• 🌸 PR title is meaningful (if it should be in the changelog: is it meaningful to users?)

🤖 AI (if applicable)

• The content of this PR was partly or fully generated using AI

This is an improvement originated from #15236 . I was unable to reproduce the issue in the ticket, but I noticed the account detail view was left empty. I populated the data in the top banner using the cached data (logic from accounts list) and fixed a bug preventing the error message to be shown. Also changed the second line of the error message to a more human readable one (the error from the lib is still logged).

[github-actions]

blue-Light-Screenshot test failed, but no output was generated. Maybe a preliminary stage failed.

[github-actions]

Codacy

SpotBugs

Category	Base	New
Bad practice	32	32
Correctness	60	60
Dodgy code	216	216
Experimental	1	1
Malicious code vulnerability	2	2
Multithreaded correctness	25	25
Performance	40	40
Security	19	19
Total	395	395

[github-actions]

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