Fresh start: replace with naxIO/netfox-cs-sample foundation

Complete replacement of the tactical-shooter project with the
netfox-cs-sample (MIT) — a CS 1.6 inspired multiplayer FPS built
with Godot 4 and netfox.

## What's new
- Full CS-style gameplay: teams (T/CT), rounds, economy, buy menu
- 6 weapons: Knife, Glock, USP, AK-47, M4A1, AWP
- Bomb plant/defuse with 2 bombsites
- Flashbang & smoke grenades
- Proper netfox rollback netcode at 64 tick
- Network popup UI for host/join
- HUD, crosshair, round timer, scoreboard
- All netfox singletons registered as autoloads (works in exported builds)

## Architecture
- Listen-server (host from client, no dedicated server binary)
- Multiplayer-fps game lives at examples/multiplayer-fps/
- Netfox addons registered as autoloads for exported build compat
- Godot 4.7 with Forward+ renderer

## Removed
- Old headless-server architecture (client_main, server_main, player.gd, etc.)
- Custom netfox bootstrap with ENet fallback
- Old ChaffGames FPS template (2,420 lines, 844 KB)
- SimulationServer GDExtension stub
- Godot-jolt physics (netfox sample uses default Godot physics)
- Duplicate weapon_data.gd, anti_cheat.gd, round_manager.gd, etc.
- Server browser API Python venv (87 MB)
- test_range map and modular assets

## Preserved
- Git history
- Server config at config/default_server_config.cfg
- Windows export preset
- Build directory (gitignored)

Co-authored-by: naxIO <naxIO@users.noreply.github.com>

docs/netfox.extras/guides/network-simulator.md

@@ -0,0 +1,80 @@
+# NetworkSimulator
+
+During testing, it is crucial to test your game under realistic network
+conditions, including latency and potentially packet loss.
+
+Network conditions can be simulated using [clumsy], [netem], or with *netfox*'s
+*NetworkSimulator*. It auto-connects instances when launched from the editor,
+and simulates various network configurations.
+
+## How to Use
+
+Enable and configure *Autoconnect* in the project settings.
+
+![Autoconnect Project settings](../assets/network-simulator.png)
+
+When your game launches one instance will start an [ENetMultiplayerPeer] server
+and the rest will connect to it.
+
+Either a `NetworkSimulator.server_created` or
+`NetworkSimulator.client_connected` signal will be fired which you can use to
+bootstrap your game code to.
+
+!!!note
+    *NetworkSimulator* will only work when the game is ran from the editor.
+    Otherwise it will disable itself, regardless of project settings. This is a
+    failsafe to avoid affecting production builds of your games.
+
+## Configuration
+
+Hostname
+: The hosting address. Usually `127.0.0.1` but can be changed to `*`, if you
+want other machines to be able to join.
+
+Server Port
+: Which port to listen on. A second server port with latency / loss will open
+one number higher if they are set to more than zero.
+
+Use Compression
+: Will make use of ENET's range encoder to keep packet sizes down.
+
+Simulated Latency ( ms )
+: Traffic delay, in milliseconds.
+
+Simlated Packet Loss Chance
+: What percentage of packets will to drop, simulating bad network conditions.
+
+## Running in CI and other environments
+
+In certain cases, you might not need the autoconnect feature to run, even if
+it's enabled in the project settings.
+
+One example could be running checks on your project in CI, or wanting to run a
+single script.
+
+In these cases, Godot will still identify itself as running in editor, so the
+autoconnect feature will start hosting, keeping the process alive. This leads
+to timeout errors, or the process running indefinitely.
+
+To avoid such cases, set any of the following environment variables to any
+non-empty string:
+
+- `CI`
+- `NETFOX_CI`
+- `NETFOX_NO_AUTOCONNECT`
+
+If *NetworkSimulator* detects any of the above environment variables, it will
+deactivate, regardless of project settings.
+
+!!!tip
+    Github Actions automatically sets the `CI` environment variable.
+    *NetworkSimulator* will automatically disable itself when running in a
+    Github Actions workflow.
+
+    See the [Github blog entry] for more details.
+
+
+[clumsy]: https://jagt.github.io/clumsy/
+[netem]: https://man7.org/linux/man-pages/man8/tc-netem.8.html
+[ENetMultiplayerPeer]: https://docs.godotengine.org/en/4.1/classes/class_enetmultiplayerpeer.html
+[Github blog entry]: https://github.blog/changelog/2020-04-15-github-actions-sets-the-ci-environment-variable-to-true/