Let complete() accept coerce/preprocess schemas (fix tsc -b build)

The "creatures" alias fix wraps the balance schema in z.preprocess, whose input
type is `unknown`. complete()'s `schema?: ZodType<T>` pinned input=output=T, so
T inferred as unknown and `res.data.add` failed under tsc -b (project build).

Loosen schema input to `ZodType<T, ZodTypeDef, any>` — T stays pinned to the
schema output, but coerce/preprocess/transform schemas (input ≠ T) are accepted.
Pin the advisor call's type param to BalanceSuggestion, matching the other
complete<...> call sites.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/features/assistant/useEncounterAdvisor.ts

@@ -127,7 +127,7 @@ export function useEncounterAdvisor(campaign: Campaign, encounter: Encounter) {
 
       if (canUseLlm) {
         const prompt = buildBalancePrompt(ctx, { difficulty: current, targetDifficulty: target, candidates });
-        const res = await complete(getLlmConfig(), { system: prompt.system, user: prompt.user, schema: balanceSuggestionSchema });
+        const res = await complete<BalanceSuggestion>(getLlmConfig(), { system: prompt.system, user: prompt.user, schema: balanceSuggestionSchema });
         if (res.ok && 'data' in res) {
           const valid = res.data.add.filter((a) => candidates.some((c) => c.name === a.name));
           if (valid.length) {