G5: bump engine (regex tooling), showcase grouping/patch/validators

Engine pointer -> d044caf (formula gene grouping, content patches, def
field validation). Game-side demonstration of all three:

- genes.json: GeneHardiness whose effect is gsum('Gene.*Tolerance') — a
  derived trait summing all tolerance genes via regex grouping.
- patches.json: a content patch giving every Bush* plant a wood harvest
  product, applied to Core's own defs at load.
- GameContent registers load-time validators: Gene/Product defNames must
  carry their type prefix.
- Program: a --check-content headless mode that loads all mod defs (running
  patches + validators) and computes a sample genome's traits (compiling
  every gene formula, grouping included) — a CI-friendly content lint.

Verified: --check-content reports 6 def types, 18 genes, 8 plants, 18
traits with hardiness computed from the gene group. Full suite green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/LittleSim/Content/GameContent.cs

@@ -62,6 +62,14 @@ public sealed class GameContent
         defs.RegisterType<PlantDef>("Plant");
         defs.RegisterType<PawnDef>("Pawn");
         defs.RegisterType<WorldPresetDef>("WorldPreset");
+        // Валидация имён при загрузке (фаза G5): гены и продукты обязаны иметь префикс типа.
+        defs.RegisterValidator("Gene", "defName", "^Gene", "gene defName must start with 'Gene'");
+        defs.RegisterValidator(
+            "Product",
+            "defName",
+            "^Product",
+            "product defName must start with 'Product'"
+        );
         defs.Load(mods);
 
         var languages = new LanguageManager(defaultLanguage: "ru");

src/LittleSim/Program.cs

@@ -1,8 +1,35 @@
+using LittleSim.Content;
 using LittleSim.Scenes;
 using Microsoft.Xna.Framework;
 using MrGameEng.Core;
+using MrGameEng.Genetics;
 using MrGameEng.Host;
 
+// Контент-линт без окна/GPU: грузит моды/дефы (патчи и валидаторы тоже), компилирует формулы генов
+// (включая группировку gsum) и выходит. Удобно для CI.
+if (args.Contains("--check-content"))
+{
+    try
+    {
+        var content = GameContent.Load();
+        var genes = content.Defs.All<GeneDef>();
+        var registry = genes.ToDictionary(g => g.DefName, g => g, StringComparer.Ordinal);
+        var traits = Phenotype.Compute(Genome.Generate(genes, new Random(1)), registry);
+        Console.WriteLine(
+            $"content ok: {content.Defs.TypeKeys.Count} def types, {genes.Count} genes, "
+                + $"{content.Defs.NamesOf("Plant").Count} plants, {traits.Count} traits "
+                + $"(hardiness={traits.GetValueOrDefault("hardiness"):0.##})"
+        );
+        return;
+    }
+    catch (Exception error)
+    {
+        Console.Error.WriteLine($"content FAILED: {error.Message}");
+        Environment.Exit(1);
+        return;
+    }
+}
+
 // Контент Core-мода грузится уже в окне — на загрузочном экране (BootScene), в фоне.
 using var host = new GameHost(
     new GameHostOptions