feat(cli): add `serve` as alias for `studio` subcommand

[christso]

Objective

Add agentv serve as an alias for agentv studio. Both commands start the same HTTP server (AgentV Studio dashboard).

Motivation

agentv studio is the current subcommand for starting the dashboard. This works well for local dev use, but when deploying to a server (e.g. OpenShift/Kubernetes), serve better communicates "long-running HTTP server process."

Precedent: tools that deploy their dashboard to servers use serve/server (Grafana, Argo CD), while studio is associated with local-only dev tools (Prisma, Drizzle). Since AgentV Studio runs in both contexts, having serve as the server-oriented alias makes the Dockerfile and deployment docs more intuitive:

CMD ["agentv", "serve"]     # clear intent: start an HTTP server
CMD ["agentv", "studio"]    # also works, same thing

Implementation

One-line alias in `apps/cli/src/index.ts`:

studio: resultsServeCommand,
serve: resultsServeCommand,   // alias

Acceptance Criteria

• `agentv serve` starts the Studio dashboard (same as `agentv studio`)
• `agentv serve --help` shows the same options as `agentv studio --help`
• `agentv studio` continues to work unchanged
• `agentv --help` lists both subcommands (or just `serve` with a note about the alias)