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)

client/tools/validate_map/README.md

@@ -0,0 +1,88 @@
+# Map Validator Scripts
+
+Validator scripts for Tactical Shooter map scenes. Run against any `.tscn` file to
+check structural integrity, performance budget, and lighting correctness before
+packaging.
+
+## Usage
+
+```bash
+# From the project root or anywhere with --path pointing at the Godot project
+godot --path client --script tools/validate_map.gd -- res://maps/mymap.tscn
+```
+
+The `--` separates Godot engine args from user args. The scene path must be a
+`res://`-prefixed Godot resource path.
+
+## Exit Codes
+
+| Code | Meaning        | Description                               |
+|------|----------------|-------------------------------------------|
+| 0    | PASS           | All checks passed, no warnings            |
+| 1    | WARNINGS       | Passed with non-blocking suggestions      |
+| 2    | ERRORS         | Failed — must-fix items found             |
+
+Use exit codes in CI/CD pipelines to gate map merges:
+```bash
+godot --path client --script tools/validate_map.gd -- res://maps/mymap.tscn
+if [ $? -eq 2 ]; then
+    echo "Map validation FAILED — fix errors before submitting"
+    exit 1
+fi
+```
+
+## Validator Modules
+
+### 1. Scene Structure (`validate_scene.gd`)
+- Scene root is a `Node3D`
+- Required node types present: `WorldEnvironment`, `LightmapGI`
+- Required Godot groups assigned to one node each: `ct_spawn`, `t_spawn`, `buy_zone`, `bomb_site`, `cubemap_origin`
+- Node naming follows PascalCase convention
+
+### 2. Polygon Count (`validate_polycount.gd`)
+- Total mesh triangle count across all `MeshInstance3D` nodes ≤ **50,000**
+- Per-mesh breakdown printed for debugging
+- Warns on individual meshes exceeding 5K triangles
+- Warns if no `MeshInstance3D` nodes found (empty map)
+
+### 3. Texture Sizes (`validate_textures.gd`)
+- All material textures (albedo, normal, roughness, metallic, ORM, emission, AO) ≤ **1024×1024**
+- Checks `StandardMaterial3D`, `ORMMaterial3D`, and `ShaderMaterial` (Texture2D params)
+- Warns on textures > 512×512 (suggested for secondary surfaces)
+- LightmapGI baked textures checked separately
+
+### 4. Lights & Lightmap (`validate_lights.gd`)
+- Dynamic (non-baked) `OmniLight3D` + `SpotLight3D` ≤ **4**
+- `DirectionalLight3D` counts toward dynamic budget if light_bake_mode ≠ Static
+- `LightmapGI` node present and baked (light_data ≠ null)
+- Lightmap quality, bounces, texel scale, and max texture size checked
+- `WorldEnvironment` configured with Environment resource
+- `ReflectionProbe` presence and settings
+- Warns on dynamic lights with shadows enabled (performance cost)
+
+## Architecture
+
+```
+client/tools/
+├── validate_map.gd              # Main entry point: parses args, loads scene, runs modules
+└── validate_map/
+    ├── validate_scene.gd         # Scene structure validator
+    ├── validate_polycount.gd     # Polygon count validator
+    ├── validate_textures.gd      # Texture size validator
+    └── validate_lights.gd        # Light/lightmap validator
+```
+
+All modules are `@tool` `RefCounted` scripts exporting a single `validate(scene_root: Node, scene_path: String) -> Dictionary` function.
+
+## Adding a New Validator
+
+1. Create `tools/validate_map/validate_<name>.gd` extending `RefCounted`
+2. Implement `func validate(scene_root: Node, scene_path: String) -> Dictionary`
+3. Return `{"pass": bool, "errors": [String], "warnings": [String]}`
+4. Add a `_run_module("<name>", instance, scene_path)` call in `validate_map.gd:_ready()`
+
+## Requirements
+
+- Godot 4.x
+- The map scene must be self-contained (all resources accessible via `res://` paths)
+- Run from a terminal (not embedded in a running game)