feat: BindableFloat — universal value source binding for all scalar properties

Introduce BindableFloat abstraction that allows any numeric property to be
either a static value or dynamically driven by a ValueSource. Backward-compatible
serialization: plain float when unbound, {value, source_id} dict when bound.

Backend:
- storage/bindable.py — BindableFloat dataclass + bfloat() helper
- 25+ scalar properties converted across all entity types
- Runtime VS acquisition in ColorStripStreamManager for CSS bindings
- All stream hot loops use self.resolve() for live values
- KeyColorsColorStripStream now inherits ColorStripStream

Frontend:
- BindableScalarWidget (slider + VS picker toggle) for all editors
- TypeScript BindableFloat type + helpers
- Graph editor edges for all bindable properties
- Audio source channel IconSelect grid

Fixes: daylight longitude, candlelight wind_strength/candle_type from_dict

server/src/wled_controller/static/locales/en.json

@@ -1,5 +1,7 @@
 {
   "app.title": "LED Grab",
+  "bindable.none": "None (static value)",
+  "bindable.toggle": "Toggle value source binding",
   "app.version": "Version:",
   "app.api_docs": "API Documentation",
   "app.connection_lost": "Server unreachable",
@@ -1331,9 +1333,12 @@
   "audio_source.parent.hint": "Multichannel source to extract a channel from",
   "audio_source.channel": "Channel:",
   "audio_source.channel.hint": "Which audio channel to extract from the multichannel source",
-  "audio_source.channel.mono": "Mono (L+R mix)",
+  "audio_source.channel.mono": "Mono",
+  "audio_source.channel.mono.desc": "L+R mix",
   "audio_source.channel.left": "Left",
+  "audio_source.channel.left.desc": "Left channel only",
   "audio_source.channel.right": "Right",
+  "audio_source.channel.right.desc": "Right channel only",
   "audio_source.description": "Description (optional):",
   "audio_source.description.placeholder": "Describe this audio source...",
   "audio_source.description.hint": "Optional notes about this audio source",
@@ -1808,6 +1813,10 @@
   "ha_light.update_rate.hint": "How often to send color updates to HA lights (0.5-5.0 Hz). Lower values are safer for HA performance.",
   "ha_light.transition": "Transition:",
   "ha_light.transition.hint": "Smooth fade duration between colors (HA transition parameter).",
+  "ha_light.color_tolerance": "Color Tolerance:",
+  "ha_light.color_tolerance.hint": "Skip sending color updates when the RGB delta is below this threshold. Reduces HA traffic for near-static scenes.",
+  "ha_light.min_brightness_threshold": "Min Brightness Threshold:",
+  "ha_light.min_brightness_threshold.hint": "Effective output brightness below this value turns lights off completely (0 = disabled).",
   "ha_light.mappings": "Light Mappings:",
   "ha_light.mappings.hint": "Map LED ranges to HA light entities. Each mapping averages the LED segment to a single color.",
   "ha_light.mappings.add": "Add Mapping",
@@ -1830,6 +1839,9 @@
   "automations.condition.home_assistant.state": "State:",
   "automations.condition.home_assistant.match_mode": "Match Mode:",
   "automations.condition.home_assistant.hint": "Activate when a Home Assistant entity matches the specified state",
+    "automations.condition.ha.match_mode.exact.desc": "State must match exactly",
+    "automations.condition.ha.match_mode.contains.desc": "State must contain the text",
+    "automations.condition.ha.match_mode.regex.desc": "State must match the regex pattern",
   "color_strip.clock": "Sync Clock:",
   "color_strip.clock.hint": "Link to a sync clock to synchronize animation timing across sources. Speed is controlled on the clock.",
   "graph.title": "Graph",