fix(cli): improve namespace inspect member list display

[geovannewashington]

What changed?

Improved the member list display in namespace inspect:

• Members are now sorted alphabetically by email, matching the UI
• Replaced hardcoded %-12s padding with tabwriter for proper
  alignment with emails of any length
• Changed Members: N to Members (N): for consistency with the
  other section headers

Why

With real client data, members with long emails or usernames caused
the role column to misalign. The ordering was also inconsistent with
the UI, which sorts members alphabetically by email.

How to test

1. Start the environment with ./bin/docker-compose up -d
2. Run cli namespace inspect <namespace> on a namespace with
   multiple members
3. Verify members appear sorted alphabetically by email
4. Verify the role column is aligned regardless of email length

[github-actions]

Claude finished @geovannewashington's task in 32s —— View job

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Code Review Complete

Reviewed 1 file across code quality, security, testing, Go patterns, and architecture — no issues found. The code looks good as-is.

The changes are clean and well-scoped: alphabetical sorting by email via slices.SortFunc, tabwriter for dynamic column alignment (consistent with the existing namespaceList pattern), and a minor header format tweak. All new imports are used, and the approach matches existing conventions in the file.

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