[feat] Add slot type color definitions

- Centralized color mapping for node connection types
- Supports all ComfyUI slot types (model, clip, vae, etc.)
- Provides default fallback color

src/constants/slotColors.ts

@@ -0,0 +1,30 @@
+/**
+ * Default colors for node slot types
+ * Mirrors LiteGraph's slot_default_color_by_type
+ */
+export const SLOT_TYPE_COLORS: Record<string, string> = {
+  number: '#AAD',
+  string: '#DCA',
+  boolean: '#DAA',
+  vec2: '#ADA',
+  vec3: '#ADA',
+  vec4: '#ADA',
+  color: '#DDA',
+  image: '#353',
+  latent: '#858',
+  conditioning: '#FFA',
+  control_net: '#F8F',
+  clip: '#FFD',
+  vae: '#F82',
+  model: '#B98',
+  '*': '#AAA' // Default color
+}
+
+/**
+ * Get the color for a slot type
+ */
+export function getSlotColor(type?: string | number | null): string {
+  if (!type) return SLOT_TYPE_COLORS['*']
+  const typeStr = String(type).toLowerCase()
+  return SLOT_TYPE_COLORS[typeStr] || SLOT_TYPE_COLORS['*']
+}