Improve interactive worktree delete selection

[nettee]

Summary

• replace the delete checkbox prompt with an integrated table selector using arrow keys, Space, Enter, Esc, and Ctrl-C handling
• show all worktrees inline with dirty/updated/state/head context and non-deletable reasons
• prevent deleting main worktrees and main-branch worktrees; sort delete rows oldest-updated first

Tests

• cargo fmt --check
• cargo test
• uv run --project e2e pytest e2e/test_interactive_delete.py