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)

server/server-browser-api/venv/lib/python3.11/site-packages/setuptools/config/distutils.schema.json

@@ -0,0 +1,26 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+
+  "$id": "https://setuptools.pypa.io/en/latest/deprecated/distutils/configfile.html",
+  "title": "``tool.distutils`` table",
+  "$$description": [
+    "**EXPERIMENTAL** (NOT OFFICIALLY SUPPORTED): Use ``tool.distutils``",
+    "subtables to configure arguments for ``distutils`` commands.",
+    "Originally, ``distutils`` allowed developers to configure arguments for",
+    "``setup.py`` commands via `distutils configuration files",
+    "<https://setuptools.pypa.io/en/latest/deprecated/distutils/configfile.html>`_.",
+    "See also `the old Python docs <https://docs.python.org/3.11/install/>_`."
+  ],
+
+  "type": "object",
+  "properties": {
+    "global": {
+      "type": "object",
+      "description": "Global options applied to all ``distutils`` commands"
+    }
+  },
+  "patternProperties": {
+    ".+": {"type": "object"}
+  },
+  "$comment": "TODO: Is there a practical way of making this schema more specific?"
+}