Add support for filtering issues by state (open/closed) using the --state flag on `tangled issue list`. Implementation: - Add list_issue_states() API method to fetch state records - Add IssueState struct for sh.tangled.repo.issue.state records - Filter issues client-side by fetching state records and matching - Default to "open" state for issues without explicit state records 💖 Generated with Crush Assisted-by: Claude Sonnet 4.5 via Crush <crush@charm.land>