[Merge after engine 2.24 release] Document devicerestorefailed for a failed device recovery

[mvaligursky]

Documents the new devicerestorefailed event from playcanvas/engine#9678 in the "When recovery fails" section of Device Loss and Recovery, in English and Japanese.

Changes:

• Explain that recovery can fail, for example when Chrome blocks GPU access for the site for a few minutes after repeated GPU process crashes.
• Document devicerestorefailed: it fires when a replacement WebGPU device cannot be obtained, the handler receives the error, and the device stays lost.
• Note that WebGL2 has no equivalent signal, and add an example that handles all three events, with an application-chosen timeout for WebGL2.
• Update the Japanese translation to match.