feat(agent): richer deploy output with deployment name and links

[JackNDwyer]

Context

Part of the agent deployments beta polish (DEVX-641). Beta feedback (Ben): the end of lk agent deploy just prints Deployed agent with no indication of which deployment/version went live or where to go next. This makes the output actionable.

Changes

After a successful lk agent deploy, print:

Completed deployment of agent <name> to <deployment> (<version>)
View analytics: <link>
Test in Agent Console: <link>

• <deployment> is production when --deployment is omitted, else the deployment name.
• Agent name and live version are resolved with a single existing ListAgents call. If that lookup fails, output falls back to the minimal summary (Completed deployment of agent to <deployment>) — a successful deploy is never reported as an error.
• The Test in Agent Console link is deep-linked to the deployment via a new deployment query param on cloudConsoleURL.
• New cloudAgentURL helper builds the analytics (agent detail) link.
• Links are omitted for non-cloud projects (self-hosted / localhost), matching lk agent start.

Tests

• Extended TestCloudConsoleURL with deployment-param cases (including query-escaping).
• Added TestCloudAgentURL.
• go build, go vet, gofmt, and go test ./cmd/lk/ all clean.

Related: livekit/web#5406 (Console deployment badge), livekit/web#4660 (docs).

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