refactor: analysis workflow architecture

fix: NEXTAUTH_URL

fix: prevent project model edits from affecting default model

src/lib/model-gateway/openai-compat/common.ts

@@ -1,11 +1,12 @@
 import OpenAI, { toFile } from 'openai'
 import { getProviderConfig } from '@/lib/api-config'
+import { getInternalBaseUrl } from '@/lib/env'
 import { getImageBase64Cached } from '@/lib/image-cache'
 import type { OpenAICompatClientConfig } from '../types'
 
 function toAbsoluteUrlIfNeeded(value: string): string {
   if (!value.startsWith('/')) return value
-  const baseUrl = process.env.NEXTAUTH_URL || 'http://localhost:3000'
+  const baseUrl = getInternalBaseUrl()
   return `${baseUrl}${value}`
 }