Adds intelligent routing system that automatically selects the best agent for user queries based on conversation context. ### Changes: - Added `routerModel` column to workspace table for configurable router LLM selection - Implemented `RouterService` with conversation history analysis and agent matching logic - Created router settings UI in AI Settings page with model dropdown - Removed agent-specific thread associations - threads are now agent-agnostic - Added real-time routing status notification in chat UI with shimmer effect - Removed automatic default assistant agent creation - Renamed GraphQL operations from agent-specific to generic (e.g., `agentChatThreads` → `chatThreads`) --------- Co-authored-by: Félix Malfait <[email protected]> Co-authored-by: Félix Malfait <[email protected]>