v0.1.1

This update focuses on online Agent management and the golden‑image cloning experience.

Agent Management
Added PUT /agents/{agent_id} to the Control Plane: updates an existing Agent’s configuration (address, token, role, tags, and enabled status are fully overwritten; leaving the token empty preserves its original value; disabled Agents no longer participate in disk provisioning or scheduling).

POST /agents/probe now accepts an optional agent_id parameter: in edit scenarios, if the token is left empty, it automatically reuses the stored token from the registration record for probing.

Added an Edit button on the WebUI Agents page: uses the same two‑step probing flow in a modal overlay; disabled Agents display a Disabled badge.

Master Image Inventory & Cloning
Agents now expose GET /masters: a background daemon thread periodically scans the storage node’s master images and caches them with a lock (interval: 30 seconds).

Control Plane added GET /masters: aggregates the master‑image inventory from all enabled disk‑role storage nodes; failure of a single node does not block the overall response.

WebUI master‑image cloning has been changed to a dropdown selection: both batch creation and the Worker detail page now pick directly from the scanned master‑image list; once selected, the Worker is automatically assigned to the node hosting that master image.