Phase 7: netfox + godot-jolt stack upgrade

Stack installed:
- netfox v1.35.3 (core + extras + noray + internals)
- godot-jolt v0.16.0-stable

Architecture:
- Server: ENet transport (works headless, no netfox deps)
- Client/Editor: netfox rollback (RollbackSynchronizer, TickInterpolator)

New/modified:
- docs/migration-netfox-plan.md — migration architecture
- scripts/network/network_manager.gd — netfox-aware ENet fallback
- scripts/network/player.gd — clean base player
- client/characters/player_netfox.gd — rollback player w/ WeaponManager
- client/characters/input/player_net_input.gd — BaseNetInput subclass
- client/characters/character/fps_character_controller.gd — netfox input feed
- client/weapons/ — weapon data, registry, TacticalWeaponHitscan, WeaponManager
- client/scripts/round_replicator.gd — client-side round state bridge
- server/scripts/round_manager.gd — improved state machine
- server/scripts/plugin_api/plugin_manager.gd — refined plugin system
- config: enemy_tag, ally_tag for meatball targeting

Removed: old C++ SimulationServer GDExtension (replaced by netfox rollback)

addons/netfox.internals/editor-utils.gd

@@ -0,0 +1,44 @@
+extends Object
+class_name _NetfoxEditorUtils
+
+static func gather_properties(root: Node, callback_name: String, handler: Callable) -> Array[String]:
+	var result: Array[String] = []
+
+	var nodes: Array[Node] = root.find_children("*")
+	nodes.push_front(root)
+	for node in nodes:
+		if not node.has_method(callback_name):
+			continue
+
+		var readable_node_name := "\"%s\" (\"%s\")" % [node.name, root.get_path_to(node)]
+		if node.get(callback_name) == null:
+			result.push_back("Can't grab method \"%s\" from node %s! Is it a @tool?" % [callback_name, readable_node_name])
+			continue
+
+		var props = node.get(callback_name).call()
+		if not props is Array:
+			result.push_back("Node %s didn't return an array on calling \"%s\"" % [readable_node_name, callback_name])
+			continue
+
+		for prop in props:
+			if prop is String:
+				# Property is a string, meaning property path relative to node
+				handler.call(node, prop)
+			elif prop is Array and prop.size() >= 2:
+				# Property is a node-property tuple
+				var prop_node: Node = null
+
+				# Node can be a String, NodePath, or an actual Node
+				if prop[0] is String or prop[0] is NodePath:
+					prop_node = node.get_node(prop[0])
+				elif prop[0] is Node:
+					prop_node = prop[0]
+				else:
+					result.push_back("Node %s specified invalid node in \"%s\": %s" % [readable_node_name, callback_name, prop])
+					continue
+
+				handler.call(prop_node, prop[1])
+			else:
+				result.push_back("Node %s specified invalid property in \"%s\": %s" % [readable_node_name, callback_name, prop])
+
+	return result