Add separate permission for AMS RFID re-read (Issue #204)

- Add new `printers:ams_rfid` permission for re-reading AMS RFID tags
- Allows granting RFID re-read access without full printer control
- Operators group includes this permission by default
- Previously used `printers:control` which grants broader access
- Permission available in Settings > Users > Group Editor

Closes #204

backend/app/api/routes/printers.py

@@ -1689,7 +1689,7 @@ async def refresh_ams_slot(
     printer_id: int,
     ams_id: int,
     slot_id: int,
-    _=RequirePermissionIfAuthEnabled(Permission.PRINTERS_CONTROL),
+    _=RequirePermissionIfAuthEnabled(Permission.PRINTERS_AMS_RFID),
     db: AsyncSession = Depends(get_db),
 ):
     """Re-read RFID for an AMS slot (triggers filament info refresh)."""

backend/app/core/permissions.py

@@ -21,6 +21,7 @@ class Permission(str, Enum):
     PRINTERS_DELETE = "printers:delete"
     PRINTERS_CONTROL = "printers:control"  # Start/stop/pause/resume prints
     PRINTERS_FILES = "printers:files"  # Send files to printer
+    PRINTERS_AMS_RFID = "printers:ams_rfid"  # Re-read AMS RFID tags
 
     # Archives
     ARCHIVES_READ = "archives:read"
@@ -159,6 +160,7 @@ PERMISSION_CATEGORIES = {
         Permission.PRINTERS_DELETE,
         Permission.PRINTERS_CONTROL,
         Permission.PRINTERS_FILES,
+        Permission.PRINTERS_AMS_RFID,
     ],
     "Archives": [
         Permission.ARCHIVES_READ,
@@ -305,6 +307,7 @@ DEFAULT_GROUPS = {
             Permission.PRINTERS_DELETE.value,
             Permission.PRINTERS_CONTROL.value,
             Permission.PRINTERS_FILES.value,
+            Permission.PRINTERS_AMS_RFID.value,
             # Archives - own items only
             Permission.ARCHIVES_READ.value,
             Permission.ARCHIVES_CREATE.value,