feat(chat): #20 CombatChatTranslator - retail-faithful combat -> ChatLog templates

Subscribes to CombatState's DamageDealtAccepted / DamageTaken /
MissedOutgoing / EvadedIncoming / AttackDone / KillLanded events
and emits chat-line text into ChatLog.OnCombatLine, mirroring
holtburger's templates verbatim from references/holtburger/apps/
holtburger-cli/src/pages/game/panels/chat.rs:221-308.

Pieces:
- ChatLog: new ChatKind.Combat value; new CombatLineKind enum
  (Info / Warning / Error) on ChatEntry; OnCombatLine(text, kind)
  adapter.
- CombatChatTranslator (Core, IDisposable). Static formatters:
  FormatDamageType (slashing/piercing/bludgeoning/fire/cold/acid/
  electric/nether), FormatDamageLocation (head/chest/abdomen/
  upper arm/lower arm/hand/upper leg/lower leg/foot), FormatPercent,
  FormatAttackConditionsSuffix.
- ChatVM.RecentLinesDetailed() returns FormattedLine records with
  kind metadata so panels can render combat lines colored.
- ChatPanel switches on Kind/CombatKind: combat-Info -> yellow,
  combat-Warning -> red incoming-damage, combat-Error -> deep red,
  all others -> existing renderer.Text path.
- GameWindow constructs translator after GameEventWiring.WireAll;
  disposes in OnClosing + live-session failure path.

Templates landed:
  Attacker:  "You hit {def} for {dmg} {dtype} damage ({hp%}). [Crit]{suffix}"
  Defender:  "{atk} hit you for {dmg} {dtype} damage to your {loc} ({hp%})..."
  Evade-out: "{def} evaded your attack."
  Evade-in:  "You evaded {atk}'s attack."
  AttackErr: "Attack sequence finished with {error}."
  Kill:      synthesized "You killed {name}." + server PlayerKilled
             death-message arrives separately via ChatLog.OnPlayerKilled.

Deviations from holtburger templates (documented in source):
- DamageDealt omits Critical-hit suffix until CombatState.DamageDealt
  carries the flag (defender-side has it; attacker-side doesn't yet).
- DamageTaken omits (health%) until CombatState.DamageIncoming
  parses the wire health-percent field.
- AttackConditions suffix is implemented but always empty until the
  bitflag is plumbed into CombatState records.

18 new tests (12 translator + 4 ChatVMCombat + 2 ChatLog).
Solution total: 978 green (243 Core.Net + 639 Core + 96 UI).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/AcDream.Core/Chat/ChatLog.cs

@@ -166,6 +166,30 @@ public sealed class ChatLog
             ChannelId: 0));
     }
 
+    /// <summary>
+    /// Phase I.7: combat-translator emits a pre-formatted line. The
+    /// translator (<see cref="CombatChatTranslator"/>) subscribes to
+    /// <see cref="Combat.CombatState"/> events and renders the retail
+    /// template (e.g. "You hit Mosswart for 12 slashing damage (54.0%)
+    /// Critical hit.") and decorates the entry with a
+    /// <see cref="Combat.CombatLineKind"/> so the panel can color the
+    /// line. Maps to holtburger's <c>info().combat()</c> /
+    /// <c>warning().combat()</c> / <c>error().combat()</c> tag flow at
+    /// <c>chat.rs:221-308</c>.
+    /// </summary>
+    public void OnCombatLine(string text, Combat.CombatLineKind kind = Combat.CombatLineKind.Info)
+    {
+        Append(new ChatEntry(
+            Kind: ChatKind.Combat,
+            Sender: "",
+            Text: text,
+            SenderGuid: 0,
+            ChannelId: 0)
+        {
+            CombatKind = kind,
+        });
+    }
+
     /// <summary>Echo the player's own outbound message after local send.</summary>
     public void OnSelfSent(ChatKind kind, string text, string targetOrChannel = "")
     {
@@ -201,6 +225,14 @@ public enum ChatKind
     Popup,
     Emote,
     SoulEmote,
+    /// <summary>
+    /// Phase I.7: a combat feedback line emitted by
+    /// <see cref="CombatChatTranslator"/> from <see cref="Combat.CombatState"/>
+    /// events. The accompanying <see cref="ChatEntry.CombatKind"/> field
+    /// drives panel coloring (info / warning / error per holtburger
+    /// <c>chat.rs:221-308</c>).
+    /// </summary>
+    Combat,
 }
 
 public readonly record struct ChatEntry(
@@ -211,4 +243,11 @@ public readonly record struct ChatEntry(
     uint ChannelId)
 {
     public DateTime Received { get; init; } = DateTime.UtcNow;
+
+    /// <summary>
+    /// Phase I.7: severity bucket for <see cref="ChatKind.Combat"/>
+    /// entries. Null for every other kind. Drives the
+    /// <see cref="ChatPanel"/>'s <c>TextColored</c> color choice.
+    /// </summary>
+    public Combat.CombatLineKind? CombatKind { get; init; }
 }