Scheduled tasks: expose a per-task directory-access grant (parity with local-agent-mode's userSelectedFolders)

Local-agent-mode scheduled tasks (~/Library/Application Support/Claude/local-agent-mode-sessions/<lineage>/scheduled-tasks.json) record a static userSelectedFolders array per task — an explicit, auditable list of which directories that task can reach.

Claude Code CLI's own scheduled-tasks feature (mcp__scheduled-tasks__*, registry at ~/Library/Application Support/Claude/claude-code-sessions/<lineage>/scheduled-tasks.json) has no equivalent field — every task shows userSelectedFolders: null. Actual file access for these tasks is governed by cwd plus an approvedPermissions list, but that list only records approved Bash command strings; Read/Edit/Write access to paths outside cwd isn't recorded anywhere in the task JSON, even though it demonstrably works (granted dynamically per session).

This makes it impossible to audit "what directories can this scheduled task actually reach" from the registry alone for CLI-scheduled tasks, unlike local-agent-mode tasks. Requesting an explicit per-task directory-grant field (or at minimum, exposing accumulated Read/Edit/Write directory access the same way Bash commands are exposed via approvedPermissions) for parity and auditability.