Fresh start: replace with naxIO/netfox-cs-sample foundation

Complete replacement of the tactical-shooter project with the
netfox-cs-sample (MIT) — a CS 1.6 inspired multiplayer FPS built
with Godot 4 and netfox.

## What's new
- Full CS-style gameplay: teams (T/CT), rounds, economy, buy menu
- 6 weapons: Knife, Glock, USP, AK-47, M4A1, AWP
- Bomb plant/defuse with 2 bombsites
- Flashbang & smoke grenades
- Proper netfox rollback netcode at 64 tick
- Network popup UI for host/join
- HUD, crosshair, round timer, scoreboard
- All netfox singletons registered as autoloads (works in exported builds)

## Architecture
- Listen-server (host from client, no dedicated server binary)
- Multiplayer-fps game lives at examples/multiplayer-fps/
- Netfox addons registered as autoloads for exported build compat
- Godot 4.7 with Forward+ renderer

## Removed
- Old headless-server architecture (client_main, server_main, player.gd, etc.)
- Custom netfox bootstrap with ENet fallback
- Old ChaffGames FPS template (2,420 lines, 844 KB)
- SimulationServer GDExtension stub
- Godot-jolt physics (netfox sample uses default Godot physics)
- Duplicate weapon_data.gd, anti_cheat.gd, round_manager.gd, etc.
- Server browser API Python venv (87 MB)
- test_range map and modular assets

## Preserved
- Git history
- Server config at config/default_server_config.cfg
- Windows export preset
- Build directory (gitignored)

Co-authored-by: naxIO <naxIO@users.noreply.github.com>

examples/rollback-npc/rollback-npc.tscn

@@ -0,0 +1,37 @@
+[gd_scene load_steps=7 format=3 uid="uid://cg0vfsftxxwv0"]
+
+[ext_resource type="PackedScene" uid="uid://cngy6hs8ohodj" path="res://examples/shared/scenes/map-square.tscn" id="1_os5l0"]
+[ext_resource type="PackedScene" uid="uid://cncdbq72u50j3" path="res://examples/shared/scenes/environment.tscn" id="2_and7e"]
+[ext_resource type="Script" path="res://examples/shared/scripts/player-spawner.gd" id="3_1ga2x"]
+[ext_resource type="PackedScene" uid="uid://badtpsxn5lago" path="res://examples/shared/ui/network-popup.tscn" id="3_1tn81"]
+[ext_resource type="PackedScene" uid="uid://bl30av5bcvd4d" path="res://examples/rollback-npc/scenes/player.tscn" id="4_pr3ur"]
+[ext_resource type="PackedScene" uid="uid://n5t5ahafwaln" path="res://examples/rollback-npc/scenes/npc.tscn" id="6_3tc5x"]
+
+[node name="rollback-npc" type="Node3D"]
+
+[node name="Square Map" parent="." instance=ExtResource("1_os5l0")]
+
+[node name="Environment" parent="." instance=ExtResource("2_and7e")]
+
+[node name="Player Spawner" type="Node" parent="." node_paths=PackedStringArray("spawn_root")]
+script = ExtResource("3_1ga2x")
+player_scene = ExtResource("4_pr3ur")
+spawn_root = NodePath(".")
+
+[node name="UI" type="Control" parent="."]
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+
+[node name="Network Popup" parent="UI" instance=ExtResource("3_1tn81")]
+layout_mode = 1
+offset_left = -180.0
+offset_top = -120.0
+offset_right = 180.0
+offset_bottom = 120.0
+
+[node name="NPC" parent="." instance=ExtResource("6_3tc5x")]
+transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 6, 1, -6)