* feat(hub,cli): forward permissionMode on session resume
When a session is resumed, the cached permissionMode is now forwarded
through the Hub → Runner → CLI pipeline via a new --permission-mode
flag. Previously the mode was lost on resume, resetting to 'default'.
Each CLI flavor validates the flag value against its own allowed
permission modes (e.g. CLAUDE_PERMISSION_MODES) and rejects unknown
values. The existing --yolo flag is preserved as a shorthand.
* refactor(cli): extract buildCliArgs from startRunner
Extract the CLI argument construction logic into a standalone
exported function so it can be unit-tested independently.
No behavior change.
* test(cli): add buildCliArgs unit tests for --permission-mode
Verify that the runner correctly forwards valid permission modes
via --permission-mode, rejects invalid values, and falls back to
--yolo when no permission mode is set.
* fix(cli): let --permission-mode take precedence over --yolo
When both flags are present, --permission-mode was silently
overwritten by a later --yolo. Guard legacy flag branches with
a hasExplicitPermissionMode check so the explicit flag wins.
