feat(net): GameEventWiring — one-call glue from dispatcher to Core state

Central registration helper that wires every parsed GameEvent from the
Phase F.1 dispatcher into the appropriate Core state class:

- ChannelBroadcast / Tell / CommunicationTransientString / PopupString
  → ChatLog (H.1)
- UpdateHealth / Victim / Defender / Attacker / EvasionAttacker /
  EvasionDefender / AttackDone → CombatState (E.4)
- MagicUpdateSpell / MagicRemoveSpell / MagicUpdateEnchantment /
  MagicRemoveEnchantment / MagicDispelEnchantment /
  MagicPurgeEnchantments → Spellbook (E.5)
- WieldObject / InventoryPutObjInContainer → ItemRepository (F.2)

This is the piece that makes the dispatcher go from "thing that routes
opcodes" to "thing that populates state the UI can redraw from". Before
this, every handler had to be wired at each call site; now one call
at startup (or per-reconnect) does the whole map.

Project graph: added AcDream.Core.Net → AcDream.Core ProjectReference
so the wiring can see both the dispatcher (Net) and the state classes
(Core). Net's own tests already pull in Core indirectly, so test scope
is unchanged.

Tests (6 new, in Core.Net.Tests): verify round-trip via the actual
dispatcher. Build envelope → dispatch → assert the correct Core state
change. Covers ChannelBroadcast, UpdateHealth, MagicUpdateSpell,
WieldObject, PopupString, MagicPurgeEnchantments.

Build green, 602 tests pass (up from 596).

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

src/AcDream.Core.Net/AcDream.Core.Net.csproj

@@ -7,4 +7,7 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <RootNamespace>AcDream.Core.Net</RootNamespace>
   </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\AcDream.Core\AcDream.Core.csproj" />
+  </ItemGroup>
 </Project>