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/snippets/input-gathering-tutorial/continuous-sampled-input.gd

@@ -0,0 +1,25 @@
+extends BaseNetInput
+
+var movement: Vector3 = Vector3.ZERO
+
+var _movement_buffer: Vector3 = Vector3.ZERO
+var _movement_samples: int = 0
+
+func _process(_dt: float) -> void:
+	_movement_buffer += Vector3(
+		Input.get_axis("move_west", "move_east"),
+		Input.get_action_strength("move_jump"),
+		Input.get_axis("move_north", "move_south")
+	)
+	_movement_samples += 1
+
+func _gather() -> void:
+	# Average samples
+	if _movement_samples > 0:
+		movement = _movement_buffer / _movement_samples
+	else:
+		movement = Vector3.ZERO
+
+	# Reset buffer
+	_movement_buffer = Vector3.ZERO
+	_movement_samples = 0