feat(cli): compact mailery list output

[andrei-hasna]

Summary

• add compact default output helpers for CLI list/status surfaces, with explicit --limit, --offset, --verbose, --json/detail paths
• compact the largest default dump, mailery agent context, while keeping full output behind --verbose/--json
• add a sampled MCP agent context resource plus emails://agent/context/full for MCP-native full detail
• extend compact hints to broad inventory commands: provider, domain, address, alias, contact, template, sequence/enrollments, forwarding, group, owner, sendkey, schedule, and provision status

Before / after examples

Worst measured local command:

• before: mailery agent context -> 412 lines, 13,427 bytes
• after: mailery agent context -> 26 lines, 1,100 bytes
• detail path preserved: mailery agent context --verbose -> 412 lines, 13,427 bytes

Other measured examples:

• config list: 67 lines / 8,178 bytes before; 25 lines / 2,259 bytes after
• address list: 53 lines / 3,442 bytes before; 25 lines / 2,285 bytes after
• alias list: 40 lines / 3,092 bytes before; 24 lines / 1,817 bytes after

Validation

• bun test (1608 pass, 0 fail)
• bun run build
• bun run build:types
• targeted affected CLI/MCP tests
• adversarial CLI ergonomics review completed and reconciled

Compatibility notes

• Existing --json payloads remain the machine-readable path for CLI commands.
• Broad MCP list tool defaults were kept at their prior page size for compatibility after review.
• The compact MCP context resource now points to and registers emails://agent/context/full for full detail.