feat: implement projectile system and add nail gun, plasma gun, and DMR weapons

weapons/dmr.gd

@@ -110,3 +110,9 @@ func _input(event: InputEvent) -> void:
 func _start_reload() -> void:
 	super._start_reload()
 	is_ads = false # Drop out of ADS on reload
+
+func unequip() -> void:
+	is_ads = false
+	if camera:
+		camera.fov = default_fov
+	position = Vector3(0.3, -0.3, -0.7)

weapons/nail_gun.gd

@@ -105,13 +105,14 @@ func _spawn_custom_projectile(origin: Vector3, fire_dir: Vector3) -> void:
 	proj.add_child(mesh_instance)
 	
 	# Projectile rotation so it faces velocity
-	# (Basis looking towards fire_dir)
-	var up = Vector3.UP
-	if abs(fire_dir.dot(up)) > 0.99:
-		up = Vector3.RIGHT
-	proj.transform.basis = Basis.looking_at(fire_dir, up)
+	var up_vec = Vector3.UP
+	if abs(fire_dir.dot(up_vec)) > 0.99:
+		up_vec = Vector3.RIGHT
+	proj.transform.basis = Basis.looking_at(fire_dir, up_vec)
 	
-	proj.global_position = muzzle_flash.global_position if muzzle_flash else origin
+	proj.position = muzzle_flash.global_position if muzzle_flash else origin
+	proj.logical_source = origin
+		
 	proj.velocity = fire_dir * projectile_speed
 	proj.damage = base_damage
 	proj.min_damage = min_damage

weapons/plasma_gun.gd

@@ -90,7 +90,9 @@ func _spawn_custom_projectile(origin: Vector3, fire_dir: Vector3) -> void:
 	light.omni_range = 4.0
 	proj.add_child(light)
 	
-	proj.global_position = muzzle_flash.global_position if muzzle_flash else origin
+	proj.position = muzzle_flash.global_position if muzzle_flash else origin
+	proj.logical_source = origin
+		
 	proj.velocity = fire_dir * projectile_speed
 	proj.damage = base_damage
 	proj.min_damage = min_damage

weapons/projectile.gd

@@ -10,10 +10,14 @@ var falloff_start: float = 10.0
 var min_damage: float = 5.0
 var drop_gravity: float = 0.0 # For arc projectiles (nailgun might have slight drop, plasma none)
 
+var logical_source = null
 var _previous_position: Vector3
 
 func _ready() -> void:
-	_previous_position = global_position
+	if logical_source != null:
+		_previous_position = logical_source
+	else:
+		_previous_position = global_position
 	# Automatically destroy after 5 seconds to prevent leaks
 	var t = get_tree().create_timer(5.0)
 	t.timeout.connect(queue_free)