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/idna/compat.py

@@ -0,0 +1,41 @@
+from typing import Any, Union
+
+from .core import decode, encode
+
+
+def ToASCII(label: str) -> bytes:
+    """Compatibility shim for :rfc:`3490` ``ToASCII``.
+
+    Delegates to :func:`idna.encode` (IDNA 2008). Provided to ease porting
+    of code written against the legacy :mod:`encodings.idna` API; new code
+    should call :func:`idna.encode` directly.
+
+    :param label: The label or domain to encode.
+    :returns: The encoded form as ASCII :class:`bytes`.
+    """
+    return encode(label)
+
+
+def ToUnicode(label: Union[bytes, bytearray]) -> str:
+    """Compatibility shim for :rfc:`3490` ``ToUnicode``.
+
+    Delegates to :func:`idna.decode` (IDNA 2008). Provided to ease porting
+    of code written against the legacy :mod:`encodings.idna` API; new code
+    should call :func:`idna.decode` directly.
+
+    :param label: The label or domain to decode.
+    :returns: The decoded Unicode form.
+    """
+    return decode(label)
+
+
+def nameprep(s: Any) -> None:
+    """Stub for :rfc:`3491` Nameprep, which is not used by IDNA 2008.
+
+    IDNA 2008 (:rfc:`5891`) replaces Nameprep with the per-codepoint
+    validity classes from :rfc:`5892`; this function exists only to
+    return a clear error if legacy code attempts to call it.
+
+    :raises NotImplementedError: Always.
+    """
+    raise NotImplementedError("IDNA 2008 does not utilise nameprep protocol")