feat(timeline): add eventCardConfig accent matrix + DTO test factories

getAccentConfig(entry) maps each EVENT to its glyph (* / † / ⚭ / ★ / ◍), German
redundant-cue label, and accent kind (REQ-007/008/018). test-factories build
TimelineEntryDTO/TimelineDTO mirroring the real wire shape for component specs.

Refs #779
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/lib/timeline/eventCardConfig.ts

@@ -0,0 +1,38 @@
+import * as m from '$lib/paraglide/messages.js';
+import type { components } from '$lib/generated/api';
+
+type TimelineEntryDTO = components['schemas']['TimelineEntryDTO'];
+
+/** Styling discriminant for an axis pill/band. */
+export type TimelineAccent = 'derived' | 'curated' | 'historical';
+
+export interface AccentConfig {
+	/** Visible Unicode glyph — render `aria-hidden`, paired with an sr-only label. */
+	glyph: string;
+	/** German layer/life-event label — used as the sr-only text and as visible chrome. */
+	label: string;
+	accent: TimelineAccent;
+}
+
+/**
+ * Maps a timeline EVENT entry to its glyph, redundant non-color label, and accent
+ * (REQ-007/008/018). Derived life-events use the * / † / ⚭ glyphs that match
+ * `personLifeDates.ts`; HISTORICAL events get the muted world band; everything
+ * else (curated PERSONAL) gets the mint family pill.
+ */
+export function getAccentConfig(entry: TimelineEntryDTO): AccentConfig {
+	if (entry.derived) {
+		switch (entry.derivedType) {
+			case 'BIRTH':
+				return { glyph: '*', label: m.timeline_derived_birth(), accent: 'derived' };
+			case 'DEATH':
+				return { glyph: '†', label: m.timeline_derived_death(), accent: 'derived' };
+			case 'MARRIAGE':
+				return { glyph: '⚭', label: m.timeline_derived_marriage(), accent: 'derived' };
+		}
+	}
+	if (entry.type === 'HISTORICAL') {
+		return { glyph: '◍', label: m.timeline_layer_world(), accent: 'historical' };
+	}
+	return { glyph: '★', label: m.timeline_layer_family(), accent: 'curated' };
+}