fix(alarms): fetch/poll ceilings; truncation-semantics docs; log-format conformance

src/ZB.MOM.WW.MxGateway.Server/Configuration/GatewayOptionsValidator.cs

@@ -427,23 +427,35 @@ public sealed class GatewayOptionsValidator : OptionsValidatorBase<GatewayOption
     private static readonly string[] ValidAlarmFallbackModes = ["Auto", "ForceAlarmManager", "ForceSubtag"];
 
     private const int MinimumAlarmPollIntervalMilliseconds = 100;
+
+    // One hour. Above this the cadence stops being a cadence: int.MaxValue
+    // milliseconds is ~24 days, which silently disables alarm polling instead
+    // of reporting the misconfiguration.
+    private const int MaximumAlarmPollIntervalMilliseconds = 3_600_000;
+
     private const int MinimumMaxAlarmsPerFetch = 64;
 
+    // The worker is a 32-bit process and materializes each fetch as one BSTR
+    // plus a full XmlDocument over it, so an unbounded cap is an out-of-memory
+    // fault on the STA rather than a slow poll.
+    private const int MaximumMaxAlarmsPerFetch = 65_536;
+
     private static void ValidateAlarms(AlarmsOptions options, ValidationBuilder builder)
     {
         // Validated regardless of Enabled: both values are stamped onto every
         // worker launch environment, so a bad value is a misconfiguration even
         // before the central monitor is switched on.
-        if (options.PollIntervalMilliseconds < MinimumAlarmPollIntervalMilliseconds)
+        if (options.PollIntervalMilliseconds is < MinimumAlarmPollIntervalMilliseconds
+            or > MaximumAlarmPollIntervalMilliseconds)
         {
             builder.Add(
-                $"MxGateway:Alarms:PollIntervalMilliseconds must be greater than or equal to {MinimumAlarmPollIntervalMilliseconds}.");
+                $"MxGateway:Alarms:PollIntervalMilliseconds must be between {MinimumAlarmPollIntervalMilliseconds} and {MaximumAlarmPollIntervalMilliseconds}.");
         }
 
-        if (options.MaxAlarmsPerFetch < MinimumMaxAlarmsPerFetch)
+        if (options.MaxAlarmsPerFetch is < MinimumMaxAlarmsPerFetch or > MaximumMaxAlarmsPerFetch)
         {
             builder.Add(
-                $"MxGateway:Alarms:MaxAlarmsPerFetch must be greater than or equal to {MinimumMaxAlarmsPerFetch}.");
+                $"MxGateway:Alarms:MaxAlarmsPerFetch must be between {MinimumMaxAlarmsPerFetch} and {MaximumMaxAlarmsPerFetch}.");
         }
 
         if (!options.Enabled)