refactor: move claim to workos env claim subcommand

[nicknisi]

Summary

• Moves claim under workos env as a subcommand (workos env claim), since it's an environment lifecycle action alongside add/remove/switch/list
• Keeps a visible top-level workos claim alias for discoverability
• Updates all user-facing strings and help-json registry to reference the new canonical path

Test plan

• pnpm build passes
• pnpm test passes (1140 tests)
• pnpm typecheck passes
• Verify workos env claim works end-to-end
• Verify workos claim still works as alias
• Verify workos env --help shows claim subcommand
• Verify workos --help still shows claim