feat: statuses and ticket types take any colour from a colour picker

Settings shows a native colour picker (the palette as suggestions)
instead of the list of eleven names. The API takes a palette name, as
before, or any #rrggbb; picking a palette colour still saves its name,
so it keeps its hand-made dark version. A free colour gets one variant
per theme, computed with the `color` library (moved towards white or
black until it contrasts 3:1 with the surface) and applied with
light-dark(): a pale yellow darkens on white, a navy lightens on dark.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/presenters/src/lib/http/dto/responses.dto.ts

@@ -7,7 +7,6 @@ import {
   ProjectRole,
   ReleaseStatus,
   SprintStatus,
-  SETTING_COLORS,
   StatusCategory,
   TYPE_ICONS,
 } from '@task-stream/api/tracker/domain';
@@ -34,7 +33,10 @@ export class WorkflowStatusDto {
   @ApiProperty({ example: 'En revisión' }) name!: string;
   @ApiProperty({ enum: StatusCategory, enumName: 'StatusCategory' })
   category!: StatusCategory;
-  @ApiProperty({ enum: SETTING_COLORS, enumName: 'SettingColor' })
+  @ApiProperty({
+    description: 'A palette colour (follows the theme) or #rrggbb',
+    example: 'violet',
+  })
   color!: string;
   @ApiProperty({ description: 'Entering it needs a reason' })
   requiresReason!: boolean;
@@ -63,7 +65,10 @@ export class IssueTypeOptionDto {
   @ApiProperty({ example: 'BUG' }) id!: string;
   @ApiProperty({ example: 'Bug' }) name!: string;
   @ApiProperty({ enum: TYPE_ICONS, enumName: 'TypeIcon' }) icon!: string;
-  @ApiProperty({ enum: SETTING_COLORS, enumName: 'SettingColor' })
+  @ApiProperty({
+    description: 'A palette colour (follows the theme) or #rrggbb',
+    example: 'violet',
+  })
   color!: string;
   @ApiProperty() archived!: boolean;
   @ApiPropertyOptional({