fix: lazy DB initialization — useDb() called inside handlers, not at import

useRuntimeConfig() and better-sqlite3 were being called at module
top-level, which crashes during Nitro server startup. Now all DB
access is lazy via useDb(), and auth uses process.env directly.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/api/votes/[id].post.ts

@@ -1,7 +1,8 @@
 import { createHash } from 'crypto'
-import db from '../../utils/db'
+import { useDb } from '../../utils/db'
 
 export default defineEventHandler((event) => {
+  const db = useDb()
   const id = getRouterParam(event, 'id')
   const ip = getRequestIP(event, { xForwardedFor: true }) || 'unknown'
   const voterHash = createHash('sha256').update(ip + ':' + id).digest('hex')
@@ -10,7 +11,6 @@ export default defineEventHandler((event) => {
     db.prepare('INSERT INTO vote_log (idea_id, voter_hash) VALUES (?, ?)').run(id, voterHash)
     db.prepare('UPDATE ideas SET votes = votes + 1 WHERE id = ?').run(id)
   } catch {
-    // UNIQUE constraint = already voted
     throw createError({ statusCode: 409, statusMessage: 'Already voted' })
   }