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/uvloop/includes/consts.pxi

@@ -0,0 +1,33 @@
+cdef enum:
+    UV_STREAM_RECV_BUF_SIZE = 256000  # 250kb
+
+    FLOW_CONTROL_HIGH_WATER = 64  # KiB
+    FLOW_CONTROL_HIGH_WATER_SSL_READ = 256  # KiB
+    FLOW_CONTROL_HIGH_WATER_SSL_WRITE = 512  # KiB
+
+    DEFAULT_FREELIST_SIZE = 250
+    DNS_PYADDR_TO_SOCKADDR_CACHE_SIZE = 2048
+
+    DEBUG_STACK_DEPTH = 10
+
+
+    __PROCESS_DEBUG_SLEEP_AFTER_FORK = 1
+
+
+    LOG_THRESHOLD_FOR_CONNLOST_WRITES = 5
+    SSL_READ_MAX_SIZE = 256 * 1024
+
+
+cdef extern from *:
+    '''
+    // Number of seconds to wait for SSL handshake to complete
+    // The default timeout matches that of Nginx.
+    #define SSL_HANDSHAKE_TIMEOUT 60.0
+
+    // Number of seconds to wait for SSL shutdown to complete
+    // The default timeout mimics lingering_time
+    #define SSL_SHUTDOWN_TIMEOUT 30.0
+    '''
+
+    const float SSL_HANDSHAKE_TIMEOUT
+    const float SSL_SHUTDOWN_TIMEOUT