Standardize ASP filenames: remove underscores

Renamed 45 ASP files to follow lowercase concatenated naming convention:
- Direct handlers: save_machine_direct.asp -> savemachinedirect.asp
- USB files: checkin_usb.asp -> checkinusb.asp
- API files: api_usb.asp -> apiusb.asp
- Map files: network_map.asp -> networkmap.asp
- Printer files: printer_lookup.asp -> printerlookup.asp

Also:
- Updated 84+ internal references across all ASP and JS files
- Deleted 6 test/duplicate files (editmacine.asp, test_*.asp)
- Updated production migration guide with filename changes
- Added rename scripts for Linux (bash) and Windows (PowerShell)

displaysubnet.asp

@@ -88,7 +88,7 @@
                  			 </thead>
                   		<tbody>
                     			<tr>
-		      				<form method="post" action="./updatesubnet_direct.asp?subnetid=<%Response.Write(subnetid)%>">
+		      				<form method="post" action="./updatesubnetdirect.asp?subnetid=<%Response.Write(subnetid)%>">
                       				<th scope="row"><input class="form-control" type="text" name="vlan" size="4" value="<%Response.Write(rs("vlan"))%>"></th>
                       					<td><select name="subnettypeid"  class="btn btn-light px-3">
 									<option value="<%Response.Write(rs("subnettypeid"))%>"><%Response.Write(rs("subnettype"))%></option>