Fix Windows build: use entry.tscn as main scene, add fallback input handling

- Changed run/main_scene to entry.tscn (smart bootstrap detects headless vs display)
- client_main.gd now uses player.tscn instead of old FPS template
- Added mouse look (click-to-capture, escape-to-release) to player.gd fallback path
- Added _gather() call to player.gd fallback _physics_process() so PlayerNetInput
  is populated even without NetworkTime singleton (exported builds)
- Re-exported Windows build with same tag v0.1.0-windows

project.godot

@@ -12,7 +12,7 @@ config_version=5
 
 config/name="Tactical Shooter"
 config/description="Phase 0 — Headless Dedicated Server"
-run/main_scene="res://scenes/server/server_main.tscn"
+run/main_scene="res://scenes/entry.tscn"
 config/features=PackedStringArray("4.7", "Forward Plus")
 
 [autoload]