Prevent system sleep while remote access is enabled

[SDSLeon]

Tickets: none

• Add a "Prevent sleep during remote access" setting (default on) so the OS stays awake while the remote access server is active, not just while threads are working.
• Consolidate the sleep decision into a single policy that keeps the system awake when either a working thread or enabled remote access requires it.
• Update the systemd inhibitor to use a generic "Poracode is active" wake reason covering both cases.
• Add the toggle to the Remote Access settings section and the settings search index, with a new shared setting synced across processes.
• Localize the new strings in all 12 non-English catalogs and add tests for the setting defaults, sleep policy, inhibitor, and settings UI.