Spend favour on the city: builders, informants, militia

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

app.py

@@ -327,6 +327,8 @@ class Handler(BaseHTTPRequestHandler):
                 return "That isn't food"
             player["food"] = food
             return None
+        if path == "/api/favour":
+            return game.spend_favour(world, player, str(body.get("kind")), now)
         if path == "/api/perk":
             return game.buy_perk(player, str(body.get("perk")))
         if path == "/api/settings":
@@ -411,6 +413,7 @@ class Handler(BaseHTTPRequestHandler):
             "summary": summary,
             "city": city_view(world, now),
             "upcoming": game.event_view(world, upcoming, now) if upcoming else None,
+            "favours": game.favours(world, now),
             "history": history,
             "players": roster(world, now),
             "ledger": world["ledger"][-80:],