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>

test/netfox/properties/property-config.test.gd

@@ -0,0 +1,57 @@
+extends VestTest
+
+func get_suite_name() -> String:
+	return "PropertyConfig"
+
+const LOCAL_PEER := 1
+const REMOTE_PEER := 2
+
+func suite():
+	var local_node := SnapshotFixtures.state_node()
+	var remote_node := SnapshotFixtures.state_node()
+	remote_node.set_multiplayer_authority(REMOTE_PEER)
+
+	test("should get locally owned properties", func():
+		var properties := SnapshotFixtures.state_propery_entries(local_node)
+		var config := _PropertyConfig.new()
+		config.set_properties(properties)
+		config.local_peer_id = LOCAL_PEER
+
+		expect_equal(config.get_owned_properties(), properties)
+		expect_equal(config.get_properties_owned_by(LOCAL_PEER), properties)
+		expect_empty(config.get_properties_owned_by(REMOTE_PEER))
+	)
+
+	test("should get remote owned properties", func():
+		var properties := SnapshotFixtures.state_propery_entries(remote_node)
+		var config := _PropertyConfig.new()
+		config.set_properties(properties)
+		config.local_peer_id = REMOTE_PEER
+
+		expect_equal(config.get_properties_owned_by(REMOTE_PEER), properties)
+		expect_empty(config.get_properties_owned_by(LOCAL_PEER))
+	)
+
+	test("should get remote owned properties after ownership change", func():
+		var properties := SnapshotFixtures.state_properties()
+		var cache := PropertyCache.new(remote_node)
+		var config := _PropertyConfig.new()
+		config.set_properties_from_paths(SnapshotFixtures.state_properties(), cache)
+		config.local_peer_id = LOCAL_PEER
+
+		expect_empty(config.get_owned_properties())
+
+		# Update ownership
+		remote_node.set_multiplayer_authority(1)
+		config.set_properties_from_paths(SnapshotFixtures.state_properties(), cache)
+
+		# Convert to a list of property paths for easier comparison
+		var owned_properties := config.get_owned_properties()\
+			.map(func(it): return str(it))
+		expect_equal(owned_properties, properties)
+	)
+
+	on_finish.connect(func():
+		local_node.queue_free()
+		remote_node.queue_free()
+	)

test/netfox/properties/property-config.test.gd.uid

@@ -0,0 +1 @@
+uid://wucpfwpo6w3n

test/netfox/properties/property-entry.test.gd

@@ -0,0 +1,45 @@
+extends VestTest
+
+func get_suite_name() -> String:
+	return "PropertyEntry"
+
+func test_should_be_valid_on_known_property():
+	var property_entry := PropertyEntry.new()
+	property_entry.node = TestNode.new()
+	property_entry.property = "known_property"
+
+	expect(property_entry.is_valid(), "Property entry is invalid!")
+
+func test_should_be_valid_on_null_property():
+	var property_entry := PropertyEntry.new()
+	property_entry.node = TestNode.new()
+	property_entry.property = "null_property"
+
+	expect(property_entry.is_valid(), "Property entry is invalid!")
+
+func test_should_be_invalid_on_unknown_property():
+	var property_entry := PropertyEntry.new()
+	property_entry.node = TestNode.new()
+	property_entry.property = "unknown_property"
+
+	expect_not(property_entry.is_valid(), "Property entry is valid!")
+
+func test_should_be_invalid_on_unknown_node():
+	var property_entry := PropertyEntry.new()
+	property_entry.node = null
+	property_entry.property = "known_property"
+
+	expect_not(property_entry.is_valid(), "Property entry is valid!")
+
+func test_should_be_invalid_on_invalid_node():
+	var property_entry := PropertyEntry.new()
+	property_entry.node = TestNode.new()
+	property_entry.property = "known_property"
+
+	property_entry.node.free()
+
+	expect_not(property_entry.is_valid(), "Property entry is valid!")
+
+class TestNode extends Node:
+	var known_property := ""
+	var null_property = null

test/netfox/properties/property-entry.test.gd.uid

@@ -0,0 +1 @@
+uid://ci3ql26p3vwsi

test/netfox/properties/property-snapshot.test.gd

@@ -0,0 +1,86 @@
+extends VestTest
+
+func get_suite_name() -> String:
+	return "PropertySnapshot"
+
+func test_diff_should_be_empty():
+	# Given
+	var from := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+		"bar": 18,
+	})
+
+	var to := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+		"bar": 18,
+	})
+
+	var expected := _PropertySnapshot.from_dictionary({})
+
+	# When
+	var actual := from.make_patch(to)
+
+	# Then
+	expect_equal(actual.as_dictionary(), expected.as_dictionary())
+
+func test_diff_should_add_unknown():
+	# Given
+	var from := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+	})
+
+	var to := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+		"bar": 18,
+	})
+
+	var expected := _PropertySnapshot.from_dictionary({
+		"bar": 18,
+	})
+
+	# When
+	var actual := from.make_patch(to)
+
+	# Then
+	expect_equal(actual.as_dictionary(), expected.as_dictionary())
+
+func test_diff_should_add_differing():
+	# Given
+	var from := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+		"bar": 18,
+	})
+
+	var to := _PropertySnapshot.from_dictionary({
+		"foo": 35,
+		"bar": 18,
+	})
+
+	var expected := _PropertySnapshot.from_dictionary({
+		"foo": 35
+	})
+
+	# When
+	var actual := from.make_patch(to)
+
+	# Then
+	expect_equal(actual.as_dictionary(), expected.as_dictionary())
+
+func test_diff_should_exclude_removed():
+	# Given
+	var from := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+		"bar": 18,
+	})
+
+	var to := _PropertySnapshot.from_dictionary({
+		"foo": 15,
+	})
+
+	var expected := _PropertySnapshot.from_dictionary({})
+
+	# When
+	var actual := from.make_patch(to)
+
+	# Then
+	expect_equal(actual.as_dictionary(), expected.as_dictionary())

test/netfox/properties/property-snapshot.test.gd.uid

@@ -0,0 +1 @@
+uid://cmu1no787kjyt