Add DatePicker theme integration test and doc updates

Introduces an integration test for DatePicker theme customization with a golden screenshot for macOS. Updates docstrings for Theme class to clarify DataTableTheme and DatePickerTheme usage. Also refines ListTile hover_color docstring to specify when it takes effect.

Author: InesaFitsner

sdk/python/packages/flet/integration_tests/controls/golden/macos/date_picker_theme/theme1.png

@@ -0,0 +1,41 @@
+import datetime
+
+import pytest
+import pytest_asyncio
+
+import flet as ft
+import flet.testing as ftt
+
+
+# Create a new flet_app instance for each test method
+@pytest_asyncio.fixture(scope="function", autouse=True)
+def flet_app(flet_app_function):
+    return flet_app_function
+
+
+@pytest.mark.asyncio(loop_scope="function")
+async def test_date_picker_theme(flet_app: ftt.FletTestApp, request):
+    flet_app.page.theme = ft.Theme(
+        date_picker_theme=ft.DatePickerTheme(
+            bgcolor=ft.Colors.GREEN_200,
+        )
+    )
+
+    dp = ft.DatePicker(
+        current_date=datetime.datetime(year=2025, month=8, day=15),
+        first_date=datetime.datetime(year=2000, month=10, day=1),
+        last_date=datetime.datetime(year=2025, month=10, day=1),
+    )
+    flet_app.page.enable_screenshots = True
+    flet_app.page.window.width = 400
+    flet_app.page.window.height = 600
+    flet_app.page.show_dialog(dp)
+    flet_app.page.update()
+    await flet_app.tester.pump_and_settle()
+
+    flet_app.assert_screenshot(
+        "theme1",
+        await flet_app.page.take_screenshot(
+            pixel_ratio=flet_app.screenshots_pixel_ratio
+        ),
+    )

sdk/python/packages/flet/integration_tests/controls/test_date_picker_theme.py

@@ -115,7 +115,8 @@ class ListTile(LayoutControl, AdaptiveControl):
 
     hover_color: Optional[ColorValue] = None
     """
-    The tile's color when hovered. Only shows if `toggle_inputs` is True.
+    The tile's color when hovered. Only takes effect if `toggle_inputs` is True or if
+    `on_click` is provided.
     """
 
     selected: bool = False

sdk/python/packages/flet/src/flet/controls/material/list_tile.py

@@ -3348,7 +3348,15 @@ class Theme:
     """
 
     data_table_theme: Optional[DataTableTheme] = None
+    """
+    Customizes the appearance of [`DataTable`][flet.DataTable] across the app.
+    """
+
     date_picker_theme: Optional[DatePickerTheme] = None
+    """
+    Customizes the appearance of [`DatePicker`][flet.DatePicker] across the app.
+    """
+
     dialog_theme: Optional[DialogTheme] = None
     """
     Customizes the appearance of [`AlertDialog`][flet.AlertDialog] across the app.