Make pagination discoverable on list commands

[weppos]

Make pagination obvious on every list command, so a person (or an AI agent) can immediately see when results span multiple pages and how to fetch the rest. A customer reported that dnsimple records list silently returned only the first page, with no indication that more records existed.

billing charges is intentionally excluded: the SDK options type for that endpoint does not support paging.

Fixes #51

📋 Deployment Pre/Post tasks

N/A

Deployment Verification

• dnsimple records list <zone> on a zone with more than 30 records prints Showing 30 of N records (page 1 of M) to stderr, above the table.
• The hint is absent when output is piped/redirected (stdout stays clean) and when a single page covers all results.
• dnsimple records list <zone> --json includes a pagination object and prints no hint.
• dnsimple records list <zone> --all fetches every page and prints no hint.
• --page / --per-page work on every paginated list command (e.g. dnsimple services list --page 2).