feat(cli): add dbx node packages

docs/content/docs/cli.mdx

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+---
+title: DBX CLI
+description: Use DBX connections from terminals, scripts, CI, and Codex.
+---
+
+<Callout type="info">
+DBX CLI is a dedicated command line package for terminal, script, and coding-agent workflows. It shares DBX connection storage and SQL safety rules with the MCP server.
+</Callout>
+
+## Install
+
+```bash
+npm install -g @dbx-app/cli
+```
+
+Requires Node.js 22.13.0 or newer.
+
+Check the installed version:
+
+```bash
+dbx --version
+```
+
+## Common Commands
+
+```bash
+dbx doctor
+dbx capabilities
+dbx connections list --json
+dbx connections list --format csv
+dbx schema list local --json
+dbx schema describe local users --json
+dbx query local "select count(*) as total from users" --json
+dbx query local "select id, name from users" --format csv
+dbx query local "select * from users" --limit 50 --timeout 10s --json
+dbx query local --file ./query.sql --json
+dbx context local --tables users,orders
+dbx open local users
+```
+
+## Diagnostics
+
+Use `dbx doctor` to inspect local DBX paths, connection-store health, and whether the desktop bridge is available:
+
+```bash
+dbx doctor
+dbx doctor --json
+```
+
+If `dbx doctor` reports a `NODE_MODULE_VERSION` mismatch after switching Node.js versions, rebuild the native dependencies with the Node.js version you use to run `dbx`:
+
+```bash
+pnpm rebuild better-sqlite3 keytar --pending
+```
+
+For global npm installs, reinstall the CLI with the same Node.js version:
+
+```bash
+npm uninstall -g @dbx-app/cli
+npm install -g @dbx-app/cli
+```
+
+Use `dbx capabilities` to see which database types can be queried directly and which currently require DBX Desktop:
+
+```bash
+dbx capabilities
+dbx capabilities --json
+```
+
+Direct execution currently supports PostgreSQL/Redshift, MySQL-compatible databases (MySQL, Doris, StarRocks), and SQLite. Other database types use the DBX Desktop bridge until their drivers are added to `@dbx-app/node-core`.
+
+## Default Connection
+
+Set `DBX_CONNECTION` to omit the connection name for query and context commands:
+
+```bash
+DBX_CONNECTION=local dbx query "select 1" --json
+DBX_CONNECTION=local dbx context --tables users,orders
+```
+
+## Output Formats
+
+Use `--json` or `--format json` for stable machine-readable output. Use `--format csv` for query, connection, and schema data that should be piped into other command line tools.
+
+```bash
+dbx query local "select id, name from users" --format csv
+```
+
+Errors are written to stderr and return a non-zero exit code.
+
+## Query Controls
+
+`dbx query` executes one SQL statement. It is read-only by default.
+
+```bash
+dbx query local "select * from users" --limit 50 --timeout 10s --json
+```
+
+Durations accept `ms`, `s`, or `m`, such as `500ms`, `10s`, or `1m`.
+
+Use `--allow-writes` for non-dangerous write statements:
+
+```bash
+dbx query local "update users set name = 'Ada' where id = 1" --allow-writes
+```
+
+Dangerous SQL such as `DROP`, `TRUNCATE`, and `ALTER` requires both `--allow-writes` and `--allow-dangerous-sql`.
+
+## SQL Starting With a Dash
+
+Pass `--` before SQL that starts with a dash:
+
+```bash
+dbx query local --json -- "-- comment
+select 1"
+```
+
+## Error Codes
+
+CLI JSON errors use stable codes:
+
+| Code | Meaning |
+|---|---|
+| `UNKNOWN_OPTION` | An unsupported flag was provided |
+| `INVALID_OPTION` | A flag is missing a value or has an invalid value |
+| `INVALID_ARGUMENT` | Positional arguments are missing or conflicting |
+| `CONNECTION_STORE_ERROR` | DBX connection storage exists but could not be read |
+| `CONNECTION_NOT_FOUND` | No DBX connection matched the requested name |
+| `SQL_BLOCKED` | SQL safety rules blocked execution |
+| `DBX_NOT_RUNNING` | DBX Desktop bridge is unavailable |
+| `ERROR` | Unexpected runtime failure |
+
+## Codex
+
+Codex can call the CLI directly from shell tools:
+
+```bash
+dbx schema describe local users --json
+dbx context local --tables users,orders | codex exec "Write a retention query"
+```