Backups: collection interval is actually readable

plugins/backups/plugin.py

@@ -144,6 +144,14 @@ class BackupsPlugin(BasePlugin):
                 'description': 'Minimum hours between collection attempts on a '
                                'PC. GE-Enforce runs every cycle; the collector '
                                'skips until this much time has passed.',
+                # MUST be public. The collecting script reads this from
+                # /api/settings/public BEFORE it has any credential, and its
+                # Get-IntervalHours falls back to 24 on any failure - silently.
+                # Left off the allowlist, the setting looked configurable and
+                # was not: every PC used 24 no matter what the UI said. A
+                # collection cadence is not a secret; the share root beneath it
+                # is internal topology and stays private.
+                'public': True,
             },
             {
                 'key': 'backups_shareroot',