fix: use shared formatStatsForPrompt from backstoryGenerator

Removes duplicated local version that had different format.
Also brings backstoryGenerator.ts into the worktree from main.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/llm/backstoryGenerator.ts

@@ -0,0 +1,38 @@
+import type { Stats } from '@dflike/shared';
+import type { World } from '../ecs/World.js';
+import type { LlmService } from './llmService.js';
+
+const STAT_KEYS: (keyof Stats)[] = [
+  'strength', 'dexterity', 'constitution', 'intelligence', 'perception',
+  'sociability', 'courage', 'curiosity', 'empathy', 'temperament',
+];
+
+const STAT_ABBREVS: Record<keyof Stats, string> = {
+  strength: 'STR', dexterity: 'DEX', constitution: 'CON',
+  intelligence: 'INT', perception: 'PER',
+  sociability: 'SOC', courage: 'COU', curiosity: 'CUR',
+  empathy: 'EMP', temperament: 'TMP',
+};
+
+export function formatStatsForPrompt(stats: Stats): string {
+  return STAT_KEYS.map(k => `${STAT_ABBREVS[k]}:${Math.floor(stats[k])}`).join(', ');
+}
+
+export async function generateBackstory(
+  world: World,
+  entityId: number,
+  llmService: LlmService,
+): Promise<void> {
+  const name = world.getComponent<string>(entityId, 'name');
+  const stats = world.getComponent<Stats>(entityId, 'stats');
+  if (!name || !stats) return;
+
+  const result = await llmService.generate('backstory', {
+    npcName: name,
+    stats: formatStatsForPrompt(stats),
+  });
+
+  if (result) {
+    world.addComponent<string>(entityId, 'backstory', result);
+  }
+}

server/src/systems/narrationEmitter.ts

@@ -3,19 +3,9 @@ import type {
 } from '@dflike/shared';
 import type { World } from '../ecs/World.js';
 import type { NarrationService } from '../llm/narrationService.js';
+import { formatStatsForPrompt } from '../llm/backstoryGenerator.js';
 import { classify } from './relationshipHelpers.js';
 
-function formatStatsForPrompt(stats: Stats): string {
-  const personality = [
-    `sociability:${stats.sociability}`,
-    `courage:${stats.courage}`,
-    `curiosity:${stats.curiosity}`,
-    `empathy:${stats.empathy}`,
-    `temperament:${stats.temperament}`,
-  ];
-  return personality.join(', ');
-}
-
 export function narrationEmitter(
   world: World,
   narrationService: NarrationService,