Initial commit: Theriapolis baseline at port/godot branch point

Captures the pre-Godot-port state of the codebase. This is the rollback
anchor for the Godot port (M0 of theriapolis-rpg-implementation-plan-godot-port.md).
All Phase 0 through Phase 6.5 work is included; Phase 7 is in flight.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Theriapolis.Tests/Persistence/Phase5SaveRoundTripTests.cs

@@ -0,0 +1,104 @@
+using Theriapolis.Core;
+using Theriapolis.Core.Data;
+using Theriapolis.Core.Items;
+using Theriapolis.Core.Persistence;
+using Theriapolis.Core.Rules.Character;
+using Theriapolis.Core.Rules.Stats;
+using Xunit;
+
+namespace Theriapolis.Tests.Persistence;
+
+public sealed class Phase5SaveRoundTripTests
+{
+    private readonly ContentResolver _content = new(new ContentLoader(TestHelpers.DataDirectory));
+
+    [Fact]
+    public void Character_RoundTripsThroughCharacterCodec()
+    {
+        var c = MakeBasicCharacter();
+        // Add and equip an item so the codec hits the inventory + equip-slot path.
+        var sword = c.Inventory.Add(_content.Items["rend_sword"]);
+        c.Inventory.TryEquip(sword, EquipSlot.MainHand, out _);
+        c.Conditions.Add(Condition.Frightened);
+        c.ExhaustionLevel = 2;
+        c.CurrentHp = c.MaxHp - 3;
+        c.Xp = 142;
+
+        var snap = CharacterCodec.Capture(c);
+        var restored = CharacterCodec.Restore(snap, _content);
+
+        Assert.Equal(c.Clade.Id,        restored.Clade.Id);
+        Assert.Equal(c.Species.Id,      restored.Species.Id);
+        Assert.Equal(c.ClassDef.Id,     restored.ClassDef.Id);
+        Assert.Equal(c.Background.Id,   restored.Background.Id);
+        Assert.Equal(c.Abilities.STR,   restored.Abilities.STR);
+        Assert.Equal(c.Abilities.WIS,   restored.Abilities.WIS);
+        Assert.Equal(c.Level,           restored.Level);
+        Assert.Equal(c.Xp,              restored.Xp);
+        Assert.Equal(c.MaxHp,           restored.MaxHp);
+        Assert.Equal(c.CurrentHp,       restored.CurrentHp);
+        Assert.Equal(c.ExhaustionLevel, restored.ExhaustionLevel);
+        Assert.Contains(Condition.Frightened, restored.Conditions);
+        Assert.Single(restored.Inventory.Items);
+        Assert.Equal("rend_sword", restored.Inventory.Items[0].Def.Id);
+        Assert.Equal(EquipSlot.MainHand, restored.Inventory.Items[0].EquippedAt);
+        Assert.Same(restored.Inventory.Items[0], restored.Inventory.GetEquipped(EquipSlot.MainHand));
+
+        // Skill set should match (set equality)
+        Assert.Equal(c.SkillProficiencies, restored.SkillProficiencies);
+    }
+
+    [Fact]
+    public void SaveBody_PlayerCharacter_RoundTripsThroughSaveCodec()
+    {
+        var c = MakeBasicCharacter();
+        var snap = CharacterCodec.Capture(c);
+
+        var header = new SaveHeader { Version = C.SAVE_SCHEMA_VERSION, WorldSeedHex = "0xFEED" };
+        var body   = new SaveBody { PlayerCharacter = snap };
+        // Player is not interesting for this test; clock + chunks empty.
+        body.Player.Id = 1;
+        body.Player.Name = "Tester";
+
+        var bytes = SaveCodec.Serialize(header, body);
+        var (h2, body2) = SaveCodec.Deserialize(bytes);
+
+        Assert.Equal(header.Version, h2.Version);
+        Assert.NotNull(body2.PlayerCharacter);
+        Assert.Equal(snap.CladeId,   body2.PlayerCharacter!.CladeId);
+        Assert.Equal(snap.SpeciesId, body2.PlayerCharacter.SpeciesId);
+        Assert.Equal(snap.ClassId,   body2.PlayerCharacter.ClassId);
+        Assert.Equal(snap.STR,       body2.PlayerCharacter.STR);
+        Assert.Equal(snap.WIS,       body2.PlayerCharacter.WIS);
+        Assert.Equal(snap.MaxHp,     body2.PlayerCharacter.MaxHp);
+    }
+
+    [Fact]
+    public void SaveBody_NoCharacter_StillRoundTrips()
+    {
+        // Phase-4-style body with no character. Round-trips cleanly because
+        // TAG_CHARACTER is only written when PlayerCharacter is non-null.
+        var header = new SaveHeader { Version = C.SAVE_SCHEMA_VERSION, WorldSeedHex = "0xDEAD" };
+        var body   = new SaveBody();
+        var bytes = SaveCodec.Serialize(header, body);
+        var (_, body2) = SaveCodec.Deserialize(bytes);
+        Assert.Null(body2.PlayerCharacter);
+    }
+
+    private Character MakeBasicCharacter()
+    {
+        var b = new CharacterBuilder
+        {
+            Clade        = _content.Clades["canidae"],
+            Species      = _content.Species["wolf"],
+            ClassDef     = _content.Classes["fangsworn"],
+            Background   = _content.Backgrounds["pack_raised"],
+            BaseAbilities = new AbilityScores(15, 14, 13, 12, 10, 8),
+            Name         = "Roundtrip",
+        };
+        // Class.SkillsChoose = 2 for fangsworn
+        b.ChosenClassSkills.Add(SkillId.Athletics);
+        b.ChosenClassSkills.Add(SkillId.Intimidation);
+        return b.Build();
+    }
+}