fix(cli): add --header flag to all CLI subcommands that make RPC calls

Summary

Many CLI subcommands that make RPC calls are missing the --header / -H flag, making it impossible to pass authentication headers (e.g., session cookies). Only create subcommands and preferences commands currently support it.

Affected commands

Expected behavior

All subcommands that make RPC calls should support --header / -H for passing authentication headers:

./frontier organization list -H "Cookie:sid=<session>"
./frontier user view <id> -H "Cookie:sid=<session>"
./frontier namespace list -H "Cookie:sid=<session>"

🤖 Generated with Claude Code

Start with the existing header handling in the CLI's create subcommands and preferences commands, then inspect the organization, project, group, user, role, permission, policy, and namespace list/view/edit entry points. Confirm that every listed subcommand making an RPC call accepts --header/-H and that the documented authentication-header examples work.