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>

sh/test.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+source sh/shared.sh
+VEST_LOG="vest.log"
+
+# Run tests
+# NOTE: Must be ran with 4.2+, so the --import flag is available
+# Otherwise, Godot won't import scripts properly
+print "::group::Import project"
+godot --headless --import .
+print "::endgroup::"
+
+print "::group::Run vest"
+godot --headless -s "addons/vest/cli/vest-cli.gd" \
+      --vest-glob "res://test/*.test.gd" \
+      --vest-report-format tap --vest-report-file "$VEST_LOG"
+print "::endgroup::"
+
+# Check results
+if [ ! -f "$VEST_LOG" ]; then
+  echo "::error::No test logs!"
+  exit 1
+fi
+
+echo "::group::Test report"
+cat "$VEST_LOG"
+echo ""
+echo "::endgroup::"
+
+if grep "not ok" "$VEST_LOG"; then
+  echo "::error::There are failing test(s)!"
+  exit 1
+else
+  print "Success!"
+fi