fix: bump maxTokens again (800/500) and add conciseness instructions

Post-restart logs show model still hitting 600-token ceiling on verbose
responses — truncated JSON at exactly 599-600 output tokens. Average
successful response was ~418 tokens but outliers reach 600+. Added
explicit conciseness instructions to backstory prompt to reduce variance.

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

server/src/llm/templates.ts

@@ -69,11 +69,12 @@ export const templates: Record<string, PromptTemplate> = {
 
   backstoryAndDesires: {
     name: 'backstoryAndDesires',
-    maxTokens: 600,
+    maxTokens: 800,
     systemPrompt:
       'Write a brief backstory (1-2 sentences) and 1-2 initial desires for this settler. ' +
       'The backstory should reflect their personality without referencing professions or institutions that do not exist. ' +
       'Desires should be grounded in what is achievable or aspirational given the current world state.\n\n' +
+      'Be concise. Keep backstory under 2 sentences. Keep desire descriptions short (under 10 words).\n\n' +
       'Respond ONLY with a valid JSON object. No explanation, no markdown, just JSON.',
     userPrompt:
       'New settler: {{npcName}}\n' +
@@ -83,7 +84,7 @@ export const templates: Record<string, PromptTemplate> = {
       '- Existing structures: {{structureList}}\n\n' +
       'Respond with JSON:\n' +
       '{"backstory": "1-2 sentence backstory", "desires": [' +
-      '{"description": "human-readable desire", ' +
+      '{"description": "short desire", ' +
       '"category": "material|social|shelter|comfort|community|creative", ' +
       '"fulfillment": {"type": "own_item|structure_exists|building_exists|relationship_tier|recipe_exists|custom", ...criteria}, ' +
       '"priority": 0.0-1.0}]}',
@@ -91,7 +92,7 @@ export const templates: Record<string, PromptTemplate> = {
 
   desireGeneration: {
     name: 'desireGeneration',
-    maxTokens: 400,
+    maxTokens: 500,
     systemPrompt:
       'Generate a new personal desire for this settler based on their personality and recent experiences.\n\n' +
       'Respond ONLY with a valid JSON object. No explanation, no markdown, just JSON.',