feat(net): port retail physics spawn and event timestamps

Parse the complete PhysicsDesc plus F754/F755 packets, correct every PhysicsState bit, and gate all nine retail update channels with generation-safe immutable snapshots. Preserve ForcePosition, teleport, placement, velocity, parent, pickup, delete, and same-generation CreateObject ordering from the named client.

Separate accepted logical lifecycle notifications from retained UI qualities, make GUID replacement and session reset clear every projection exactly once, and add packet, wraparound, malformed-input, parent FIFO, canonical-position, reconnect, and GUID-reuse conformance coverage.

Co-Authored-By: Codex <noreply@openai.com>

src/AcDream.App/Streaming/LandblockEntityRehydrator.cs

@@ -20,9 +20,9 @@ namespace AcDream.App.Streaming;
 ///
 /// <para>
 /// acdream's dungeon-collapse (and Near→Far demote) drops a landblock's
-/// RENDER entities for FPS but retains the parsed spawns
-/// (<c>GameWindow._lastSpawnByGuid</c> — the table is only pruned by an
-/// explicit server <c>DeleteObject</c> or a spawn de-dup). On reload, ACE will
+/// RENDER entities for FPS but retains the accepted immutable spawns in
+/// <c>InboundPhysicsStateController.Snapshots</c> (pruned by an explicit server
+/// <c>DeleteObject</c> or session teardown). On reload, ACE will
 /// not re-send the objects it still thinks we have, so the render side stays
 /// empty — the #138 symptom. This selects the retained spawns whose render
 /// entity is currently absent so <c>GameWindow</c> can replay them, making