Export default CSR subject fields from core-cli device-id-cmd

## Problem

The `deviceIdRegisterEvento` handler in `@fireproof/core-cli` accepts a `ReqDeviceIdRegister` with subject fields (`country`, `organization`, `locality`, `state`), but the default values for these fields are only defined inline in the cmd-ts option definitions in `cmds/device-id-cmd.js`:

```js
country: option({ defaultValue: () => "WD" }),
organization: option({ defaultValue: () => "You did not set the Organization" }),
locality: option({ defaultValue: () => "You did not set the City" }),
state: option({ defaultValue: () => "You did not set the State" }),
```

When calling `deviceIdRegisterEvento.handle()` directly (instead of shelling out to `core-cli deviceId register`), callers must duplicate these defaults. The server rejects empty strings — e.g. `country` must be >= 2 chars.

## Request

Export a `defaultCsrSubject` constant (or similar) from `@fireproof/core-cli` so direct callers can use it:

```ts
export const defaultCsrSubject = {
country: "WD",
organization: "You did not set the Organization",
locality: "You did not set the City",
state: "You did not set the State",
};
```

## Context

vibes.diy CLI switched from shelling out to `core-cli deviceId register` to calling `deviceIdRegisterEvento.handle()` directly (VibesDIY/vibes.diy#1313). Had to hardcode the defaults to avoid CSR validation errors.