initializing the files and the memory bank.

memory-bank/systemPatterns.md

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+# System Patterns
+
+## Architecture Overview
+- **Monorepo Layout:** `pnpm` workspaces with `apps/client` (Next.js dashboard + overlay), `packages/backend` (Node ingestion + realtime gateway), `packages/shared` (types, schemas).
+- **Data Flow:**
+  1. Backend worker polls YouTube Live chat through the Innertube (youtubei) API, maintaining continuation tokens.
+  2. Messages stored in-memory (and optionally SQLite) and emitted over an internal event bus.
+  3. Client dashboard fetches chat via HTTP (React Query) and pushes selection back via REST.
+  4. Overlay page listens to Server-Sent Events stream for the currently highlighted message.
+- **Realtime Delivery:** SSE chosen for one-directional updates to OBS browser source; can swap to WebSocket if bidirectional control is required later.
+- **Configuration:** Environment variables drive stream IDs and optional auth tokens; local secrets persisted in `.env.local` or config files.
+
+## Key Patterns & Practices
+- Abstract ingestion behind an interface so alternate providers (official API, headless browser) can be swapped in quickly.
+- Cache Innertube visitor data and API keys locally to reduce startup latency and handle rotations gracefully.
+- Use Zod schemas in shared package to validate external responses and internal payloads.
+- Centralized error reporting/logging with structured logs for monitoring during streams.
+- Graceful degradation: exponential backoff on fetch failures, last-known overlay message cached to disk to survive restarts.