docs: add .cursor/CLOUD.md with development guide for cloud agents

Co-authored-by: Vikhyath Mondreti <icecrasher321@users.noreply.github.com>

.cursor/CLOUD.md

@@ -0,0 +1,45 @@
+# Sim Studio - Cloud Agent Development Guide
+
+## Overview
+
+Sim Studio is a monorepo for building and deploying AI agent workflows. See `CLAUDE.md` and `README.md` for architecture, coding standards, and integration guidelines.
+
+## Services
+
+| Service | Command | Port | Notes |
+|---------|---------|------|-------|
+| Next.js app | `bun run dev` (from root) | 3000 | Main application |
+| Socket.IO realtime | `bun run dev:sockets` (from `apps/sim`) | 3002 | Collaborative editing |
+| Both together | `bun run dev:full` (from `apps/sim` or root) | 3000, 3002 | Recommended for development |
+| Docs | `bun run dev` (from `apps/docs`) | 3001 | Optional documentation site |
+| PostgreSQL + pgvector | Docker container | 5432 | Required database |
+
+## Key Commands
+
+- **Lint**: `bun run lint:check` (biome check, no auto-fix) or `bun run lint` (with auto-fix)
+- **Format**: `bun run format:check` or `bun run format` (with auto-fix)
+- **Test**: `bun run test` (runs vitest via turbo across packages)
+- **Type-check**: `bun run type-check` (runs tsc --noEmit via turbo)
+- **Dev**: `bun run dev:full` from root or `apps/sim` (starts Next.js + Socket.IO)
+
+## Database
+
+- PostgreSQL with pgvector extension, connection via `DATABASE_URL` in `.env` files
+- Migrations: `cd packages/db && bunx drizzle-kit migrate --config=./drizzle.config.ts`
+- Schema push (no migration files): `cd packages/db && bunx drizzle-kit push --config=./drizzle.config.ts`
+- Two `.env` files are needed: `apps/sim/.env` and `packages/db/.env` (both need `DATABASE_URL`)
+
+## Testing
+
+- Framework: Vitest (config at `apps/sim/vitest.config.ts`)
+- Use `@sim/testing` mocks/factories (see `.cursor/rules/sim-testing.mdc`)
+- Tests run in parallel with thread pool
+- Run specific test: `cd apps/sim && bunx vitest run path/to/test.test.ts`
+
+## Important Notes
+
+- Package manager is **bun** (not npm/pnpm). Use `bun` and `bunx` commands.
+- The docs app requires `fumadocs-mdx` generation before type-check: `cd apps/docs && bunx fumadocs-mdx`
+- Pre-commit hook runs `bunx lint-staged` which applies biome check with auto-fix
+- Social provider warnings (GitHub/Google missing clientId) during startup are expected in local dev
+- Redis warnings ("REDIS_URL not configured") are expected - app runs in single-pod mode locally