refactor(dock): extract DockItem into items.py, remove TYPE_CHECKING

DockItem, DockModel, DockHitTest moved to items.py.
layout.py and animator.py now import directly — no circular deps.

src/window/dock/animator.py

@@ -1,16 +1,13 @@
-from typing import TYPE_CHECKING, Optional
+from typing import Optional
 
 from fabric.utils import GLib
 
 from .constants import ANIM_INTERVAL_MS, IDLE_THRESHOLD, LERP_FACTOR
 from .layout import DockLayout
 
-if TYPE_CHECKING:
-    from .canvas import DockCanvas
-
 
 class DockAnimator:
-    def __init__(self, canvas: "DockCanvas"):
+    def __init__(self, canvas):
         self._canvas = canvas
         self._timer_id: Optional[int] = None
         self._running = False

src/window/dock/canvas.py

@@ -1,5 +1,4 @@
 import math
-from dataclasses import dataclass
 from typing import Dict, List, Optional, Tuple
 
 import cairo
@@ -52,81 +51,9 @@ from .constants import (
     SEPARATOR_COLOR,
     SEPARATOR_WIDTH,
 )
+from .items import DockHitTest, DockItem, DockModel
 from .layout import DockLayout
 
-
-@dataclass
-class DockItem:
-    app_id: str
-    app_data: object
-    is_pinned: bool = False
-    is_trash: bool = False
-
-    is_running: bool = False
-    instance_address: Optional[str] = None
-    app_class: Optional[str] = None
-    client_data: Optional[dict] = None
-    workspace_id: Optional[int] = None
-
-    pixbuf: Optional[GdkPixbuf.Pixbuf] = None
-    tooltip: str = ""
-
-    current_scale: float = MIN_SCALE
-    target_scale: float = MIN_SCALE
-
-    render_x: float = 0.0
-    render_y: float = 0.0
-    render_w: float = 0.0
-    render_h: float = 0.0
-
-    drag_index: int = 0
-    is_dragging: bool = False
-
-    def hit(self, mx: float, my: float) -> bool:
-        return (
-            self.render_x <= mx <= self.render_x + self.render_w
-            and self.render_y <= my <= self.render_y + self.render_h
-        )
-
-
-class DockModel:
-    def __init__(self):
-        self.items: List[DockItem] = []
-
-    def get_by_address(self, address: str) -> Optional[DockItem]:
-        for item in self.items:
-            if item.instance_address == address:
-                return item
-        return None
-
-    def get_by_id(self, app_id: str) -> Optional[DockItem]:
-        for item in self.items:
-            if item.app_id.lower() == app_id.lower():
-                return item
-        return None
-
-    def pinned_items(self) -> List[DockItem]:
-        return [i for i in self.items if i.is_pinned]
-
-    def running_only_items(self) -> List[DockItem]:
-        return [i for i in self.items if not i.is_pinned and not i.is_trash]
-
-    def has_running_only(self) -> bool:
-        return any(not i.is_pinned and not i.is_trash for i in self.items)
-
-    def has_pinned(self) -> bool:
-        return any(i.is_pinned for i in self.items)
-
-
-class DockHitTest:
-    @staticmethod
-    def find_item(items: List[DockItem], mx: float, my: float) -> Optional[DockItem]:
-        for item in reversed(items):
-            if item.hit(mx, my):
-                return item
-        return None
-
-
 _PIXBUF_CACHE_MAX = 64
 
 

src/window/dock/items.py

@@ -0,0 +1,78 @@
+from dataclasses import dataclass
+from typing import Optional
+
+from fabric.utils import GdkPixbuf
+
+from .constants import MIN_SCALE
+
+
+@dataclass
+class DockItem:
+    app_id: str
+    app_data: object
+    is_pinned: bool = False
+    is_trash: bool = False
+
+    is_running: bool = False
+    instance_address: Optional[str] = None
+    app_class: Optional[str] = None
+    client_data: Optional[dict] = None
+    workspace_id: Optional[int] = None
+
+    pixbuf: Optional[GdkPixbuf.Pixbuf] = None
+    tooltip: str = ""
+
+    current_scale: float = MIN_SCALE
+    target_scale: float = MIN_SCALE
+
+    render_x: float = 0.0
+    render_y: float = 0.0
+    render_w: float = 0.0
+    render_h: float = 0.0
+
+    drag_index: int = 0
+    is_dragging: bool = False
+
+    def hit(self, mx: float, my: float) -> bool:
+        return (
+            self.render_x <= mx <= self.render_x + self.render_w
+            and self.render_y <= my <= self.render_y + self.render_h
+        )
+
+
+class DockModel:
+    def __init__(self):
+        self.items: list[DockItem] = []
+
+    def get_by_address(self, address: str) -> Optional[DockItem]:
+        for item in self.items:
+            if item.instance_address == address:
+                return item
+        return None
+
+    def get_by_id(self, app_id: str) -> Optional[DockItem]:
+        for item in self.items:
+            if item.app_id.lower() == app_id.lower():
+                return item
+        return None
+
+    def pinned_items(self) -> list[DockItem]:
+        return [i for i in self.items if i.is_pinned]
+
+    def running_only_items(self) -> list[DockItem]:
+        return [i for i in self.items if not i.is_pinned and not i.is_trash]
+
+    def has_running_only(self) -> bool:
+        return any(not i.is_pinned and not i.is_trash for i in self.items)
+
+    def has_pinned(self) -> bool:
+        return any(i.is_pinned for i in self.items)
+
+
+class DockHitTest:
+    @staticmethod
+    def find_item(items: list[DockItem], mx: float, my: float) -> Optional[DockItem]:
+        for item in reversed(items):
+            if item.hit(mx, my):
+                return item
+        return None

src/window/dock/layout.py

@@ -1,5 +1,4 @@
 import math
-from typing import TYPE_CHECKING
 
 from .constants import (
     BG_PADDING_H,
@@ -10,15 +9,13 @@ from .constants import (
     MIN_SCALE,
     SIGMA_FACTOR,
 )
-
-if TYPE_CHECKING:
-    from .canvas import DockItem
+from .items import DockItem
 
 
 class DockLayout:
     @staticmethod
     def compute(
-        items: "list[DockItem]",
+        items: list[DockItem],
         mouse_x: float,
         _mouse_y: float,
         base_icon_size: int,
@@ -72,11 +69,11 @@ class DockLayout:
 
     @staticmethod
     def background_rect(
-        items: "list[DockItem]",
+        items: list[DockItem],
         base_icon_size: int,
         canvas_w: int,
         canvas_h: int,
-    ) -> "tuple[float, float, float, float]":
+    ) -> tuple[float, float, float, float]:
         bg_h = base_icon_size + 2 * BG_PADDING_V
         bg_y = canvas_h - INDICATOR_H - bg_h