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>

addons/netfox/servers/data/property-pool.gd

@@ -0,0 +1,64 @@
+extends RefCounted
+class_name _PropertyPool
+
+# Stores a set of properties, with each property belonging to a subject
+
+var _properties_by_subject := {} # object to property array
+
+static func of(entries: Array[Array]) -> _PropertyPool:
+	var pool := _PropertyPool.new()
+
+	for entry in entries:
+		var subject := entry[0] as Object
+		var property := entry[1] as NodePath
+		pool.add(subject, property)
+
+	return pool
+
+func add(subject: Object, property: NodePath) -> void:
+	if has(subject, property):
+		return
+
+	if not _properties_by_subject.has(subject):
+		_properties_by_subject[subject] = [property]
+	else:
+		_properties_by_subject[subject].append(property)
+
+func has(subject: Object, property: NodePath) -> bool:
+	return (_properties_by_subject.get(subject, []) as Array).has(property)
+
+func erase(subject: Object, property: NodePath) -> void:
+	if not _properties_by_subject.has(subject):
+		return
+
+	var props := _properties_by_subject[subject] as Array
+	props.erase(property)
+
+	if props.is_empty():
+		_properties_by_subject.erase(subject)
+
+func erase_subject(subject: Object) -> void:
+	_properties_by_subject.erase(subject)
+
+func clear() -> void:
+	_properties_by_subject.clear()
+
+func get_properties_of(subject: Object) -> Array[NodePath]:
+	var properties := [] as Array[NodePath]
+	properties.assign(_properties_by_subject.get(subject, []))
+	return properties
+
+func get_subjects() -> Array[Object]:
+	var subjects := [] as Array[Object]
+	subjects.assign(_properties_by_subject.keys())
+	return subjects
+
+func is_empty() -> bool:
+	return _properties_by_subject.is_empty()
+
+func set_from_paths(root: Node, paths: Array[String]) -> void:
+	clear()
+
+	for path in paths:
+		var prop := PropertyEntry.parse(root, path)
+		add(prop.node, prop.property)