Feature: Snapshot-Tab in Datasets mit Kontextmenü (Clone/Rename/Rollback/Destroy)

- Snapshots direkt im Datasets-Tab ladbar (lazy, per Pool)
- Tabelle: Name, Created, Used, Referenced, Clones
- Kontextmenü (⋮) mit Clone, Rename, Roll Back, Destroy Snapshot
- Backend: /api/snapshots/clone + /api/snapshots/rename Endpoints

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/routers/snapshots.py

@@ -35,6 +35,14 @@ class CreateSnapshotRequest(BaseModel):
 class RollbackSnapshotRequest(BaseModel):
     snapshot: str
 
+class CloneSnapshotRequest(BaseModel):
+    snapshot: str
+    target: str  # full target dataset name
+
+class RenameSnapshotRequest(BaseModel):
+    snapshot: str
+    new_name: str  # new snapshot tag (after @)
+
 
 @router.get("/", response_model=List[Snapshot])
 async def list_snapshots(
@@ -96,6 +104,44 @@ async def delete_snapshot(
         raise HTTPException(status_code=500, detail=str(e))
 
 
+@router.post("/clone")
+async def clone_snapshot(
+    request: CloneSnapshotRequest,
+    current_user: str = Depends(get_current_user)
+):
+    """Clone snapshot to a new dataset"""
+    try:
+        result = zfs_runner.run_command(["zfs", "clone", request.snapshot, request.target])
+        if result[2] != 0:
+            raise HTTPException(status_code=400, detail=result[1])
+        zfs_runner.clear_cache()
+        return {"status": "success", "message": f"Cloned to {request.target}"}
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post("/rename")
+async def rename_snapshot(
+    request: RenameSnapshotRequest,
+    current_user: str = Depends(get_current_user)
+):
+    """Rename snapshot"""
+    try:
+        dataset = request.snapshot.split("@")[0]
+        new_full = f"{dataset}@{request.new_name}"
+        result = zfs_runner.run_command(["zfs", "rename", request.snapshot, new_full])
+        if result[2] != 0:
+            raise HTTPException(status_code=400, detail=result[1])
+        zfs_runner.clear_cache()
+        return {"status": "success", "message": f"Renamed to {new_full}"}
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
 @router.post("/rollback")
 async def rollback_snapshot(
     request: RollbackSnapshotRequest,