Metin2 game client (P0–P11) + mobile asset pipeline

Networked client on the existing Godot 4.7 + libgr2 renderer:
- net: m2dev wire protocol (libsodium KX + XChaCha20), auth/select/game
  phases, EntityStore world model, ~all GC/CG headers. char create/delete,
  private shop / mall / cube, SHOP_GC_START_EX, guild, party (+ CG_PARTY_SET_STATE),
  quests, dragon soul, refine, safebox, exchange.
- UI: in-game windows migrated 1:1 from the reference uiscript/root .py —
  char status (/stat), inventory+equipment, select-item ([SELECT_ITEM] quest
  token), system-option + game-option + ESC system menu, private-shop 39-grid,
  party info board, shop tabs, atlas, minimap, quickbar, chat, …
- EterGrnLib polish: GR2 material blend/two-sided, LOD crossfade, motion-event
  dispatch, contact shadow, ray-AABB picking, weapon grip pre-transform.

Portable asset IO (A1) — all extension/libgr2/formats/mtproto reads routed
through godot::FileAccess (res:// PCK works on iOS/Android); standalone-lib
*_path() kept for the non-Godot CTests. AssetResolver + PropertyRegistry
switched to a baked index (bake_asset_index.gd) instead of std::filesystem.

Mobile builds: build-{android,ios}.sh, export-android.sh, pack-assets.sh,
gen-debug-keystore.sh. Assets ship as a zip mounted at runtime by
project/asset_pack.gd (adb push now; HTTP download is a drop-in later).

ctest 10/10, 34 GDScript suites, macOS/iOS/Android all build.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013EJxkHiNKS4kybHS3XKyAJ

project/ui/friend_ui.gd

@@ -0,0 +1,107 @@
+# FriendUI (P8) —— 好友 / 私聊名单窗（M 键）。
+#
+#   var fu := preload("res://ui/friend_ui.gd").new()
+#   add_child(fu)
+#   fu.setup(m2client, canvas_parent)
+#   fu.toggle()    # M 键
+#
+# 每行 = 在线点 + 名字 + [删除]。底部输入框 + [添加好友]。
+# `friends_changed` 刷新。双击某行 → emit `whisper_to(name)`（chat_ui 可接）。
+extends Node
+
+signal whisper_to(name: String)
+
+var client: Node
+var _root: Control
+var _list: VBoxContainer
+var _name_edit: LineEdit
+
+func setup(m2client: Node, parent: Node) -> void:
+	client = m2client
+	_build(parent)
+	if client.has_signal("friends_changed"):
+		client.friends_changed.connect(refresh)
+
+func is_open() -> bool:
+	return _root != null and _root.visible
+
+func toggle() -> void:
+	_root.visible = not _root.visible
+	if _root.visible:
+		refresh()
+
+func refresh() -> void:
+	if not is_open() or client == null:
+		return
+	for c in _list.get_children():
+		c.queue_free()
+	var friends: Array = client.get_friends()
+	if friends.is_empty():
+		var e := Label.new()
+		e.text = "（好友列表为空）"
+		e.add_theme_font_size_override("font_size", 11)
+		_list.add_child(e)
+		return
+	for f in friends:
+		_list.add_child(_row(f))
+
+func _row(f: Dictionary) -> Control:
+	var row := HBoxContainer.new()
+	row.custom_minimum_size = Vector2(260, 0)
+	var dot := Label.new()
+	dot.text = "●"
+	dot.modulate = Color(0.4, 0.9, 0.4) if f.get("online", false) else Color(0.4, 0.4, 0.4)
+	row.add_child(dot)
+	var nm := Button.new()
+	nm.text = String(f.get("name", "?"))
+	nm.flat = true
+	nm.custom_minimum_size = Vector2(180, 0)
+	nm.pressed.connect(func() -> void: whisper_to.emit(String(f.get("name", ""))))
+	row.add_child(nm)
+	var del := Button.new()
+	del.text = "×"
+	del.pressed.connect(func() -> void: client.remove_friend(String(f.get("name", ""))))
+	row.add_child(del)
+	return row
+
+func _on_add() -> void:
+	var nm := _name_edit.text.strip_edges()
+	if nm != "":
+		client.add_friend(nm)
+		_name_edit.clear()
+
+func _build(parent: Node) -> void:
+	_root = Control.new()
+	_root.set_anchors_preset(Control.PRESET_CENTER)
+	_root.position = Vector2(-150, -180)
+	_root.size = Vector2(300, 360)
+	_root.visible = false
+	_root.set_meta("is_titlebar", true)
+	parent.add_child(_root)
+	var panel := Panel.new()
+	panel.set_anchors_preset(Control.PRESET_FULL_RECT)
+	var sb := StyleBoxFlat.new()
+	sb.bg_color = Color(0.07, 0.08, 0.1, 0.96)
+	sb.set_corner_radius_all(4)
+	panel.add_theme_stylebox_override("panel", sb)
+	_root.add_child(panel)
+	var title := Label.new()
+	title.text = "好友"
+	title.position = Vector2(12, 8)
+	_root.add_child(title)
+	_list = VBoxContainer.new()
+	_list.position = Vector2(12, 34)
+	_list.add_theme_constant_override("separation", 3)
+	_root.add_child(_list)
+	var bottom := HBoxContainer.new()
+	bottom.position = Vector2(12, 320)
+	bottom.custom_minimum_size = Vector2(276, 0)
+	_root.add_child(bottom)
+	_name_edit = LineEdit.new()
+	_name_edit.placeholder_text = "角色名"
+	_name_edit.custom_minimum_size = Vector2(190, 0)
+	bottom.add_child(_name_edit)
+	var add_btn := Button.new()
+	add_btn.text = "添加"
+	add_btn.pressed.connect(_on_add)
+	bottom.add_child(add_btn)