Initial commit — Station 0 vertical slice in progress

Includes full design documentation (ARCHITECTURE, DESIGN_NOTES, CONTENT_SPEC, PRODUCTION_NOTES)
and active Godot 4 / GDScript codebase. Core systems built: player, floor generation,
room system, enemy base, body part upgrades, run manager, save system, HUD, EventBus.

scripts/enemies/enemy_base.gd

@@ -0,0 +1,76 @@
+extends CharacterBody2D
+
+# ---------------------------------------------------------------------------
+# Stats — override in derived enemy types
+# ---------------------------------------------------------------------------
+var max_health:       float = 10.0
+var current_health:   float = 10.0
+var speed:            float = 60.0
+var contact_damage:   float = 1.0
+var contact_cooldown: float = 0.8
+
+# ---------------------------------------------------------------------------
+# Internal state
+# ---------------------------------------------------------------------------
+var _contact_timer: float = 0.0
+var _flash_timer:   float = 0.0
+var _player: Node2D = null
+
+@onready var visual: Node2D = $Visual
+
+func _ready() -> void:
+	add_to_group("enemies")
+	$ContactArea.body_entered.connect(_on_contact_entered)
+
+func _physics_process(delta: float) -> void:
+	_contact_timer = maxf(_contact_timer - delta, 0.0)
+	_tick_flash(delta)
+	_chase_player()
+	move_and_slide()
+
+# ---------------------------------------------------------------------------
+# AI — simple chaser
+# ---------------------------------------------------------------------------
+func _chase_player() -> void:
+	if _player == null or not is_instance_valid(_player):
+		_player = get_tree().get_first_node_in_group("player")
+	if _player != null:
+		velocity = (_player.global_position - global_position).normalized() * speed
+	else:
+		velocity = Vector2.ZERO
+
+# ---------------------------------------------------------------------------
+# Damage / death
+# ---------------------------------------------------------------------------
+func take_damage(amount: float) -> void:
+	current_health -= amount
+	_flash_timer = 0.1
+	if current_health <= 0.0:
+		_die()
+
+func _die() -> void:
+	_spawn_drop()
+	queue_free()
+
+func _spawn_drop() -> void:
+	var orb = preload("res://scenes/enemies/currency_orb.tscn").instantiate()
+	orb.position = (get_parent() as Node2D).to_local(global_position)
+	get_parent().call_deferred("add_child", orb)
+
+# ---------------------------------------------------------------------------
+# Contact damage
+# ---------------------------------------------------------------------------
+func _on_contact_entered(body: Node) -> void:
+	if body.is_in_group("player") and _contact_timer == 0.0:
+		body.take_damage(contact_damage)
+		_contact_timer = contact_cooldown
+
+# ---------------------------------------------------------------------------
+# Hit flash
+# ---------------------------------------------------------------------------
+func _tick_flash(delta: float) -> void:
+	if _flash_timer > 0.0:
+		_flash_timer -= delta
+		visual.modulate = Color(2.5, 2.5, 2.5)
+	else:
+		visual.modulate = Color(1.0, 1.0, 1.0)