Add repository-level AGENT.md guidance for coding agents

AGENT.md

@@ -0,0 +1,53 @@
+# Agent Guide
+
+This repository is `@bquery/ui`, a framework-agnostic Web Components library built with TypeScript, Vite, Bun, Storybook, and VitePress.
+
+## What lives where
+
+- `src/components/` – component implementations
+- `src/tokens/` – design tokens
+- `src/theme/` – theme helpers and CSS variables
+- `src/i18n/` – localization utilities
+- `src/utils/` – shared helpers
+- `docs/` – VitePress documentation
+- `stories/` – Storybook stories
+- `tests/` – Bun-based test suite
+
+## Preferred workflow
+
+1. Keep changes focused and consistent with existing component patterns.
+2. Update documentation when behavior or public APIs change.
+3. Avoid unrelated refactors while addressing a targeted issue.
+4. Prefer accessibility, composability, and API consistency improvements.
+
+## Setup and validation
+
+Install dependencies with Bun:
+
+```bash
+bun install --frozen-lockfile
+```
+
+If Bun is not installed globally in your environment, use:
+
+```bash
+npx bun install --frozen-lockfile
+```
+
+Use these commands to validate work:
+
+```bash
+npm run lint:types
+npm run test
+npm run build
+npm run build:docs
+```
+
+If Bun is not installed globally, use `npx bun test` instead of `npm run test`.
+
+## Project-specific notes
+
+- `bun.lock` is the source of truth for dependencies; `package-lock.json` is ignored.
+- Tests preload `tests/setup.ts` through `bunfig.toml`.
+- Documentation uses Markdown in `docs/` and the root `README.md`.
+- Storybook stories live in `stories/` and should stay aligned with component behavior.

README.md

@@ -146,10 +146,12 @@ See [`docs/guide/framework-integration.md`](./docs/guide/framework-integration.m
 ## Local Development
 
 ```bash
-npm ci
+bun install --frozen-lockfile
 npm run dev
 ```
 
+If Bun is not installed globally in your environment, use `npx bun install --frozen-lockfile`.
+
 ### Available scripts
 
 ```bash
@@ -184,6 +186,7 @@ When contributing:
 1. Keep changes focused and consistent with the existing component patterns.
 2. Validate type safety, documentation, and affected component behavior.
 3. Prefer additions that improve accessibility, composability, or API consistency.
+4. If you are working as an automated coding agent, follow the repository-specific guidance in [`AGENT.md`](./AGENT.md), including the canonical Bun workflow.
 
 ## License