feat: web search

[sadaf-labs]

Problem:
Users need real‑time web search inside chats, but current flows lack an integrated SERP lookup—requiring separate DataforSEO calls and manual result passing.

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Solution:

• New /api/chat/web-search endpoint that:

  1. Checks DataforSEO connectivity
  2. Fetches and normalizes live Google SERP via DataforSEO
  3. Wraps results in a web_search_tool message for Azure OpenAI

• ChatInput toggle (“Web search”) to route queries through /api/chat/web-search when enabled

• Handler update to merge web‑search replies into the existing chat stream

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Environment Variables:

NEXT_PUBLIC_DATAFORSEO_LOGIN=your_login  
NEXT_PUBLIC_DATAFORSEO_PASSWORD=your_password  
AZURE_OPENAI_KEY=your_azure_api_key  
AZURE_OPENAI_ENDPOINT=https://your-resource.openai.azure.com  
AZURE_GPT_45_TURBO_NAME=your_deployment_name