Fix: Samba config PUT 422 + shadow:format setparm dash escaping

Route /samba/{name} was matching before /samba/config, causing 422 on
PUT /samba/config. Moved static routes before parameterized routes.

Values starting with '-' (shadow: format = -%Y-%m-%d-%H%M) were parsed
as CLI flags by net conf setparm. Added '--' separator to escape them.

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

backend/routers/shares.py

@@ -78,6 +78,31 @@ async def create_samba_share(
         raise HTTPException(status_code=500, detail=str(e))
 
 
+@router.get("/samba/config")
+async def get_samba_config(current_user: str = Depends(get_current_user)):
+    """Get Samba global configuration"""
+    try:
+        config = share_manager.get_samba_global_config()
+        return config
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.put("/samba/config")
+async def set_samba_config(
+    request: SambaConfigRequest,
+    current_user: str = Depends(get_current_user)
+):
+    """Update Samba global configuration parameters"""
+    try:
+        success = share_manager.set_samba_global_config(request.parameters)
+        if not success:
+            raise HTTPException(status_code=400, detail="Failed to update Samba configuration")
+        return {"status": "updated"}
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
 @router.put("/samba/{name}")
 async def update_samba_share(
     name: str,
@@ -116,31 +141,6 @@ async def delete_samba_share(
         raise HTTPException(status_code=500, detail=str(e))
 
 
-@router.get("/samba/config")
-async def get_samba_config(current_user: str = Depends(get_current_user)):
-    """Get Samba global configuration"""
-    try:
-        config = share_manager.get_samba_global_config()
-        return config
-    except Exception as e:
-        raise HTTPException(status_code=500, detail=str(e))
-
-
-@router.put("/samba/config")
-async def set_samba_config(
-    request: SambaConfigRequest,
-    current_user: str = Depends(get_current_user)
-):
-    """Update Samba global configuration parameters"""
-    try:
-        success = share_manager.set_samba_global_config(request.parameters)
-        if not success:
-            raise HTTPException(status_code=400, detail="Failed to update Samba configuration")
-        return {"status": "updated"}
-    except Exception as e:
-        raise HTTPException(status_code=500, detail=str(e))
-
-
 @router.post("/samba/config/import")
 async def import_samba_config(
     request: SambaImportRequest,