[Cursor] Development environment setup (#7088)

* [AI] Add Cursor Cloud specific instructions to AGENTS.md

Co-authored-by: Matiss Janis Aboltins <MatissJanis@users.noreply.github.com>

* [autofix.ci] apply automated fixes

* Add release notes for PR #7088

* [AI] Fix Node.js minimum version requirement in AGENTS.md (#7089)

* [AI] Fix outdated Node.js version requirement in Build Failures section

Co-authored-by: Matiss Janis Aboltins <MatissJanis@users.noreply.github.com>

* [AI] Add test budget tip to Cursor Cloud instructions

Co-authored-by: Matiss Janis Aboltins <MatissJanis@users.noreply.github.com>

---------

Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: Matiss Janis Aboltins <MatissJanis@users.noreply.github.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>

AGENTS.md

@@ -529,7 +529,7 @@ Icons in `packages/component-library/src/icons/` are auto-generated. Don't manua
 
 1. Clean build artifacts: `rm -rf packages/*/dist packages/*/lib-dist packages/*/build`
 2. Reinstall dependencies: `yarn install`
-3. Check Node.js version (requires >=20)
+3. Check Node.js version (requires >=22)
 4. Check Yarn version (requires ^4.9.1)
 
 ## Testing Patterns
@@ -619,7 +619,7 @@ yarn install:server
 
 ## Environment Requirements
 
-- **Node.js**: >=20
+- **Node.js**: >=22
 - **Yarn**: ^4.9.1 (managed by packageManager field)
 - **Browser Targets**: Electron >= 35.0, modern browsers (see browserslist)
 
@@ -632,3 +632,40 @@ The codebase is actively being migrated:
 - **React.\* → Named Imports**: Legacy React.\* patterns being removed
 
 When working with older code, follow the newer patterns described in this guide.
+
+## Cursor Cloud specific instructions
+
+### Services overview
+
+| Service             | Command                 | Port | Required                      |
+| ------------------- | ----------------------- | ---- | ----------------------------- |
+| Web Frontend (Vite) | `yarn start`            | 3001 | Yes                           |
+| Sync Server         | `yarn start:server-dev` | 5006 | Optional (sync features only) |
+
+All storage is **SQLite** (file-based via `better-sqlite3`). No external databases or services are needed.
+
+### Running the app
+
+- `yarn start` builds the plugins-service worker, loot-core browser backend, and starts the Vite dev server on port **3001**.
+- `yarn start:server-dev` starts both the sync server (port 5006) and the web frontend together.
+- The Vite HMR dev server serves many unbundled modules. In constrained environments, the browser may hit `ERR_INSUFFICIENT_RESOURCES`. If that happens, use `yarn build:browser` followed by serving the built output from `packages/desktop-client/build/` with proper COOP/COEP headers (`Cross-Origin-Opener-Policy: same-origin`, `Cross-Origin-Embedder-Policy: require-corp`).
+
+### Lint, test, typecheck
+
+Standard commands documented in `package.json` scripts and the Quick Start section above:
+
+- `yarn lint` / `yarn lint:fix` (uses oxlint + oxfmt)
+- `yarn test` (lage across all workspaces)
+- `yarn typecheck` (tsc + lage typecheck)
+
+### Testing and previewing the app
+
+When running the app for manual testing or demos, use **"View demo"** on the initial setup screen (after selecting "Don't use a server"). This creates a test budget pre-populated with realistic sample data (accounts, transactions, categories, and budgeted amounts), which is far more useful than starting with an empty budget.
+
+### Gotchas
+
+- The `engines` field requires **Node.js >=22** and **Yarn ^4.9.1**. The `.nvmrc` specifies `v22/*`.
+- Pre-commit hook runs `lint-staged` (oxfmt + oxlint) via Husky. Run `yarn prepare` once after install to set up hooks.
+- Lage caches test results in `.lage/`. If tests behave unexpectedly, clear with `rm -rf .lage`.
+- Native modules (`better-sqlite3`, `bcrypt`) require build tools (`gcc`, `make`, `python3`). These are pre-installed in the Cloud VM.
+- All yarn commands must be run from the repository root, never from child workspaces.

upcoming-release-notes/7088.md

@@ -0,0 +1,6 @@
+---
+category: Maintenance
+authors: [MatissJanis]
+---
+
+Add Cursor Cloud setup instructions and troubleshooting tips to AGENTS.md documentation.