feat(agent): Refactor agent architecture to enhance content routing and file search capabilities

- Introduced ContentRouterAgent to determine the next step in information gathering (file search, web search, or analysis) based on task relevance and focus mode.
- Added FileSearchAgent to handle searching through attached files, processing file content into searchable documents.
- Updated SynthesizerAgent to utilize a prompt template for generating comprehensive responses based on context and user queries.
- Enhanced TaskManagerAgent to consider file context when creating tasks.
- Improved AnalyzerAgent to assess the sufficiency of context, including file and web documents.
- Implemented utility functions for processing files and ranking documents based on similarity to queries.
- Updated prompts to include new instructions for handling file context and routing decisions.
- Adjusted agent search workflow to integrate new agents and support file handling.

src/app/api/search/route.ts

@@ -142,6 +142,7 @@ export const POST = async (req: Request) => {
       promptData.systemInstructions,
       signal,
       promptData.personaInstructions,
+      body.focusMode,
     );
 
     if (!body.stream) {