Canopy change: boolean flag (e.g. grayed out checkbox) for PSK verification

Behavior: when saving the PSK in a PMP450 or 450i, the PSK is removed from the WebUI and there is no indication that it was saved.

Right now, Cambium support says that "it is designed to work this way". Great, well it was designed poorly. There is no way for us to know that the PSK is saved or will actively be tried when taking the SM from the lab to the field. All we need is an indicator: either a box that says the PSK is non-empty, or a couple of black dots to fill the PSK box (it doesn't have to match the number of characters in the box if you want to be ultra-tight on security).

Honestly, our team would prefer to be able to view what the PSK is at any time, like in the ePMP1000s' WebUI.

When a PSK value is set, right next to the input box there will be a string that says "(Key Set)".  If the key  is set back to the default of all 0xFF, then it will say "(Using All 0xFF's Key)".  So there is an indicator there already.

The reason that the box isn't populated on read was a security measure taken when this feature was added since you could simply see the key by inspecting the page source.  If we return something else in that field itself, then the subsequent save changes would send that as new input.

That being said, this convention wasn't followed with the Authentication Shared Secret, and the legacy approach to authentication key doesn't match the shared secret approach, so we will look to address that.

But for now, you should see something like this when a Key is set:


And this if it is all 0xFF (default value):