Codex/whe 15 bootstrap workspace (#1)

* feat(WHE-15): bootstrap bun workspace with app and package scaffolds

* chore(WHE-17): switch workspace typecheck to tsgo

* chore(WHE-16): configure oxlint and oxfmt no-semicolon style

* chore: address CodeRabbit review feedback

* chore: apply coderabbit fixes and add review script

* docs: add ADR decision metadata

docs/runbooks/dev-setup.md

@@ -0,0 +1,45 @@
+# Development Setup
+
+## Requirements
+
+- Bun 1.3+
+- Node.js 22+
+
+## First-time setup
+
+```bash
+bun install
+```
+
+## Workspace commands
+
+```bash
+bun run lint
+bun run lint:fix
+bun run format
+bun run format:check
+bun run typecheck
+bun run test
+bun run build
+```
+
+## App commands
+
+```bash
+bun run dev:bot
+bun run dev:miniapp
+```
+
+## Review commands
+
+```bash
+bun run review:coderabbit
+```
+
+## Notes
+
+- Type checking uses `tsgo` (`@typescript/native-preview`).
+- Linting uses `oxlint`.
+- Formatting uses `oxfmt` with no-semicolon style.
+- AI review uses CodeRabbit CLI in `--prompt-only` mode against `main`.
+- `WHE-19` will add CI checks for the same root commands.