feat: expand multiplayer, chat, and release support

- add network NPC synchronization and dialogue interactions
- add world bulletin publishing and display
- improve authentication, session refresh, and appearance sync
- synchronize player direction and movement animations
- improve input focus and progressive Web loading
- add macOS/Windows builds and deployment configuration
- include required fonts, shaders, and runtime assets

scenes/characters/network_npc.tscn

@@ -0,0 +1,18 @@
+[gd_scene load_steps=4 format=3]
+
+[ext_resource type="PackedScene" path="res://scenes/characters/npc.tscn" id="1_base"]
+[ext_resource type="Script" path="res://scenes/characters/NetworkNpc.gd" id="2_script"]
+[ext_resource type="Texture2D" path="res://assets/characters/generated/whale_researcher_v2/final_no_feet/processed/whale_researcher_no_feet_spritesheet.png" id="3_researcher"]
+
+[node name="NetworkNpc" instance=ExtResource("1_base")]
+script = ExtResource("2_script")
+showNameplate = true
+nameplateOffsetY = -72.0
+
+[node name="Sprite2D" parent="." index="0"]
+position = Vector2(0, -29)
+scale = Vector2(0.5, 0.5)
+texture_filter = 1
+texture = ExtResource("3_researcher")
+hframes = 8
+vframes = 4