Review fixes: telemetry session id per login; Framework number text

F1: the telemetry session id is new at every login. The original made one per
load of its assembly and its loader reloaded it at every login; the backend
counts new kills per (session id, character), so reusing one id across a
relog under-counted kills until the reset counter passed the old total.

F5/F6: .NET Framework never wrote a negative zero, and its fixed-point
formats (F7, F2, F0) rounded at fifteen significant digits, half away from
zero. Spawn and portal coordinates, kills_per_hour and the !report line now
format that way; the round-trip converter maps -0 to 0.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/OpenAC.MosswartMassacre/Backend/FrameworkNumberConverter.cs

@@ -58,9 +58,28 @@ internal sealed class FrameworkNumberConverter : JsonConverter
     public override object? ReadJson(JsonReader reader, Type objectType, object? existingValue, JsonSerializer serializer) =>
         throw new NotSupportedException();
 
+    /// <summary>
+    /// .NET Framework's fixed-point and number formats ("F7", "F2", "F0",
+    /// "N0" ...) for a double: the value taken to fifteen significant digits,
+    /// then rounded half away from zero to the format's decimals, and never a
+    /// negative zero. The decimal type formats exactly that way.
+    /// </summary>
+    internal static string FrameworkFixed(double value, string format, IFormatProvider provider)
+    {
+        if (!double.IsFinite(value))
+            return value.ToString(format, provider);
+        string digits = value.ToString("G15", CultureInfo.InvariantCulture);
+        return decimal.TryParse(digits, NumberStyles.Float, CultureInfo.InvariantCulture, out decimal exact)
+            ? exact.ToString(format, provider)
+            : value.ToString(format, provider);
+    }
+
     /// <summary>.NET Framework's "R" for a double: G15 if it reads back exactly, else G17.</summary>
     internal static string FrameworkRoundTrip(double value)
     {
+        // The Framework printed a negative zero as "0".
+        if (value == 0d)
+            value = 0d;
         string text = value.ToString("G15", CultureInfo.InvariantCulture);
         if (double.Parse(text, NumberStyles.Float, CultureInfo.InvariantCulture) == value)
             return text;
@@ -70,6 +89,8 @@ internal sealed class FrameworkNumberConverter : JsonConverter
     /// <summary>.NET Framework's "R" for a float: G7 if it reads back exactly, else G9.</summary>
     internal static string FrameworkRoundTrip(float value)
     {
+        if (value == 0f)
+            value = 0f;
         string text = value.ToString("G7", CultureInfo.InvariantCulture);
         if (float.Parse(text, NumberStyles.Float, CultureInfo.InvariantCulture) == value)
             return text;

src/OpenAC.MosswartMassacre/MmContext.cs

@@ -71,8 +71,13 @@ internal sealed class MmContext
     /// <summary>The character's vitae penalty in percent (0 when none), as the original's vitals frame carried it.</summary>
     public Func<int> Vitae { get; set; } = static () => 0;
 
-    /// <summary>The per-process id the original put in every telemetry frame.</summary>
-    public static string ProcessSessionId { get; } = Guid.NewGuid().ToString("N");
+    /// <summary>
+    /// The telemetry session id: a fresh GUID at every login. The original
+    /// made one per load of its assembly, and its loader reloaded the assembly
+    /// at every login; the backend counts new kills per (session id,
+    /// character), so a login that resets the kill counter needs a new id.
+    /// </summary>
+    public string TelemetrySessionId { get; set; } = Guid.NewGuid().ToString("N");
 
     /// <summary>
     /// Sees every frame the plugin hands to the socket, before the socket

src/OpenAC.MosswartMassacre/MosswartMassacrePlugin.cs

@@ -110,6 +110,7 @@ public sealed class MosswartMassacrePlugin : IAcDreamPlugin
 
         string name = _host.Automation.Character.Name;
         _context.CharacterName = name;
+        _context.TelemetrySessionId = Guid.NewGuid().ToString("N");
         _context.Settings.Load(name);
         _context.IsLoggedIn = true;
         _context.Chat.Write("Mosswart Massacre has started!");

src/OpenAC.MosswartMassacre/Streams/ChatRouter.cs

@@ -71,8 +71,11 @@ internal sealed class ChatRouter : IMmFeature
                 TimeSpan elapsed = _context.Clock.Now - _kills.StatsStartTime;
                 string report = string.Format(
                     CultureInfo.CurrentCulture,
-                    "Total Kills: {0}, Kills per Hour: {1:F2}, Elapsed Time: {2:dd\\.hh\\:mm\\:ss}, Rares Found: {3}",
-                    _kills.TotalKills, _kills.KillsPerHour, elapsed, _rares.RareCount);
+                    "Total Kills: {0}, Kills per Hour: {1}, Elapsed Time: {2:dd\\.hh\\:mm\\:ss}, Rares Found: {3}",
+                    _kills.TotalKills,
+                    FrameworkNumberConverter.FrameworkFixed(_kills.KillsPerHour, "F2", CultureInfo.CurrentCulture),
+                    elapsed,
+                    _rares.RareCount);
                 _context.Host.Log.Info($"[Mosswart Massacre] Reporting to allegiance: {report}");
                 _context.Automation.Chat.Submit($"/a {report}");
             }

src/OpenAC.MosswartMassacre/Streams/SpawnPortalStream.cs

@@ -102,9 +102,10 @@ internal sealed class SpawnPortalStream : IMmFeature
     private static (string Ns, string Ew, string Z) Format(in PluginNavigationPosition position)
     {
         const string fmt = "F7";
-        string ns = position.NorthSouth.ToString(fmt, CultureInfo.InvariantCulture);
-        string ew = position.EastWest.ToString(fmt, CultureInfo.InvariantCulture);
-        string z = ((float)(position.Elevation * 240d)).ToString("F2", CultureInfo.InvariantCulture);
+        string ns = FrameworkNumberConverter.FrameworkFixed(position.NorthSouth, fmt, CultureInfo.InvariantCulture);
+        string ew = FrameworkNumberConverter.FrameworkFixed(position.EastWest, fmt, CultureInfo.InvariantCulture);
+        // The original read the height as a float and formatted it widened to a double.
+        string z = FrameworkNumberConverter.FrameworkFixed((double)(float)(position.Elevation * 240d), "F2", CultureInfo.InvariantCulture);
         return (ns, ew, z);
     }
 }

src/OpenAC.MosswartMassacre/Streams/TelemetryStream.cs

@@ -64,13 +64,13 @@ internal sealed class TelemetryStream : IMmFeature, IBackendConnectionListener
             type = "telemetry",
             character_name = _context.CharacterName,
             char_tag = _context.Settings.Current.CharTag ?? "",
-            session_id = MmContext.ProcessSessionId,
+            session_id = _context.TelemetrySessionId,
             timestamp = Wire.Timestamp(_context.Clock),
             ew = coords.EW,
             ns = coords.NS,
             z = coords.Z,
             kills = kills.TotalKills,
-            kills_per_hour = kills.KillsPerHour.ToString("F0", CultureInfo.CurrentCulture),
+            kills_per_hour = FrameworkNumberConverter.FrameworkFixed(kills.KillsPerHour, "F0", CultureInfo.CurrentCulture),
             onlinetime = (_context.Clock.Now - kills.StatsStartTime).ToString(@"dd\.hh\:mm\:ss", CultureInfo.InvariantCulture),
             deaths = kills.SessionDeaths.ToString(CultureInfo.CurrentCulture),
             total_deaths = kills.TotalDeaths.ToString(CultureInfo.CurrentCulture),