cli: add `npx convex project create` (#53256)

Adds a top-level `project` command group with a `create` subcommand — the first CLI command that can create a **project** (not just a deployment within an existing one). Fully non-interactive.

```
npx convex project create my-app --team my-team
```

`project create` only creates the project; provisioning a deployment is a separate, explicit step. After creating, it prints the exact next command:

```
npx convex deployment create <team>:<project>:dev --type dev
```

This keeps `project create` and `deployment create` orthogonal — `project create` doesn't have to mirror every deployment setting (region, class, …).

### Behavior

- Creates the project only; prints the explicit `deployment create` next step.
- Non-interactive-first: `--team` is a flag; a missing project name or unresolvable team fail fast with a clear message outside a TTY instead of hanging on a prompt.
- `--team` is the only option.

### Scope (first cut)

`create` only. Follow-ups: `--select` on `deployment create` to write env + select in one shot, and `project list` / `project settings`.

GitOrigin-RevId: c3ae1108970c9403ccf01e278d7a04b16e6a3125