dsh-treekeeper: DSH Process Tree Reconciliation and Governance Plugin

`dsh-treekeeper` is a plugin that resolves discrepancies between DSH task ledgers and OS process trees. It detects leaked and orphaned processes through process sampling and ownership analysis, and supports safe governance. The plugin supports the Windows platform, providing a visual dashboard and tree-wide termination. To prevent accidental termination, it implements strict pre-termination validation and multi-layer safeguards (such as identity checks, snapshot comparison, and non-terminable lists), ensuring that critical system services are not affected during process cleanup.