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Here's script code you can use for locking/unlocking. Copy and paste the code in the text document and save the files as lock.jsx and unlock.jsx.

Then put them in the Presets>Scripts folder in the Photoshop application folder. Restart Photoshop. Then assign your KB shortcut.

Lock Layer:

var idsetd = charIDToTypeID( "setd" );

    var desc20 = new ActionDescriptor();

    var idnull = charIDToTypeID( "null" );

        var ref15 = new ActionReference();

        var idLyr = charIDToTypeID( "Lyr " );

        var idOrdn = charIDToTypeID( "Ordn" );

        var idTrgt = charIDToTypeID( "Trgt" );

        ref15.putEnumerated( idLyr, idOrdn, idTrgt );

    desc20.putReference( idnull, ref15 );

    var idT = charIDToTypeID( "T   " );

        var desc21 = new ActionDescriptor();

        var idlayerLocking = stringIDToTypeID( "layerLocking" );

            var desc22 = new ActionDescriptor();

            var idprotectAll = stringIDToTypeID( "protectAll" );

            desc22.putBoolean( idprotectAll, true );

        var idlayerLocking = stringIDToTypeID( "layerLocking" );

        desc21.putObject( idlayerLocking, idlayerLocking, desc22 );

    var idLyr = charIDToTypeID( "Lyr " );

    desc20.putObject( idT, idLyr, desc21 );

executeAction( idsetd, desc20, DialogModes.NO );

UnLock Layer:

var idsetd = charIDToTypeID( "setd" );

    var desc23 = new ActionDescriptor();

    var idnull = charIDToTypeID( "null" );

        var ref16 = new ActionReference();

        var idLyr = charIDToTypeID( "Lyr " );

        var idOrdn = charIDToTypeID( "Ordn" );

        var idTrgt = charIDToTypeID( "Trgt" );

        ref16.putEnumerated( idLyr, idOrdn, idTrgt );

    desc23.putReference( idnull, ref16 );

    var idT = charIDToTypeID( "T   " );

        var desc24 = new ActionDescriptor();

        var idlayerLocking = stringIDToTypeID( "layerLocking" );

            var desc25 = new ActionDescriptor();

            var idprotectNone = stringIDToTypeID( "protectNone" );

            desc25.putBoolean( idprotectNone, true );

        var idlayerLocking = stringIDToTypeID( "layerLocking" );

        desc24.putObject( idlayerLocking, idlayerLocking, desc25 );

    var idLyr = charIDToTypeID( "Lyr " );

    desc23.putObject( idT, idLyr, desc24 );

executeAction( idsetd, desc23, DialogModes.NO );

I'll need to figure out the code for the layer style part. Let me know if you get the locking stuff working first.

Copy Layer Style:

var idCpFX = charIDToTypeID( "CpFX" );

executeAction( idCpFX, undefined, DialogModes.NO );

Paste layer Style:

var idPaFX = charIDToTypeID( "PaFX" );

    var desc49 = new ActionDescriptor();

    var idallowPasteFXOnLayerSet = stringIDToTypeID( "allowPasteFXOnLayerSet" );

    desc49.putBoolean( idallowPasteFXOnLayerSet, true );

executeAction( idPaFX, desc49, DialogModes.NO );