docs(algobot-cli): correct auth commands and document EU-only prod host

[itsdanwilli]

Two documentation corrections to algobot-cli, both hit while using the skill to add a search tool to a live Agent Studio agent.

1. prod resolves to the EU host

v2.0.0 hardcodes three API hosts:

env	host
prod	agent-studio.eu.algolia.com
staging	agent-studio-staging.eu.algolia.com
dev	conversational-ai-dev.algolia.com

There is no region flag, and the only environment variables the CLI reads are ALGOLIA_APP_ID, ALGOLIA_APPLICATION_ID, ALGOLIA_API_KEY and ALGOLIA_AGENT_ID — none override the host.

For an app whose agents are not in EU, this surfaces as:

$ algobot agents list
[]
$ algobot agents get <agent-id>
HTTP 404 Not Found: {"message":"Agent with ID <agent-id> not found."}

…for an agent that is live and serving completions. An empty array reads as "this app has no agents", so the natural next step is to go looking for a credential problem. Swapping in an admin API key changes nothing. The added note points at algobot --verbose agents list so the host can be confirmed first.

The skill currently documents --env dev|staging|prod|local as the environment control, which reasonably reads as covering this.

2. The auth guidance is stale

algobot auth show was removed in v2.0 and now prints a deprecation notice:

❌ The 'auth' command has been removed.
Please use the modern profiles system

Credentials also live in ~/.algobot-profiles, not ~/.algobot-cookie. Updated both the Gotchas entry and references/commands.md to profiles list / profiles show, and noted that profiles show prints the API key in plaintext — easy to leak into a screenshare or a log.

Notes

• Verified against algobot-ai 2.0.0.
• scripts/validate_skills.py passes, 129/0.
• Docs only; no behaviour change.
• I've raised the region behaviour with the Agent Studio team separately. If a supported way to target a non-EU region already exists, the first note should be reworded rather than merged as-is — happy to revise.