Smooth graphs, sun path card, skeleton page switches and editor drag & drop

Firmware 0.2.15: trend graphs use a Catmull-Rom curve with a soft fill
drawn by the card's draw event; sun.sun gets a wide sun-path card with
horizon, arc and the sun at its current position; page switches show
the new page's card frames immediately and fill them from a one-shot
timer; the navigation is one full-width bar without a divider; the CYD
adopts the Guition light palette in styles and overlays.

App 0.2.13: pointer-based drag & drop (mouse and touch) to reorder tiles
in the mockup and to drop entities from the list, sticky save bar, a new
header with explained actions and a three-step guide, clearer firmware
dialog. New sun, weather and clock tiles start wide in their best view.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

screen_manager/app/core.py

@@ -30,7 +30,9 @@ TILE_BACKGROUNDS = {
 }
 
 # Display modes per domain; everything else offers standard and watch (large value).
-DISPLAYS = {'weather': ('standard', 'watch', 'forecast'), 'sensor': ('standard', 'watch', 'graph'), 'screen': ('digital', 'analog')}
+DISPLAYS = {'weather': ('standard', 'watch', 'forecast'), 'sensor': ('standard', 'watch', 'graph'), 'screen': ('digital', 'analog'), 'sun': ('standard', 'watch', 'sunpath')}
+# Displays that only work on a double-width card.
+WIDE_ONLY = ('forecast', 'sunpath')
 
 # Additive schema 1 extension. An absent object retains old firmware/YAML defaults.
 SETTING_RULES = {
@@ -114,8 +116,8 @@ def validate_layout(data):
             for key, allowed in choices.items():
                 if key in options and options[key] not in allowed:
                     raise ValueError('Ongeldige tegelinstelling: ' + key)
-            # The five-day strip only fits a double-width card.
-            if options.get('display') == 'forecast':
+            # The five-day strip and the sun path only fit a double-width card.
+            if options.get('display') in WIDE_ONLY:
                 options = {**options, 'size': 'wide'}
             if options.get('tap') == 'toggle' and domain not in {'light','switch','input_boolean','fan','media_player'}:
                 raise ValueError('Deze entiteit ondersteunt geen aan/uit-actie.')