[FIRRTL][LowerLayers] Add probe type support

[prithayan]

This PR adds the support for LowerLayers to handle probe ops, without depending on LowerXMR.
This reverts the commit that adds the LowerXMR dependency on LowerLayers.

Layers can now capture and use probe references across layer boundaries, in addition to domain types.

Following examples demonstrate the two major use cases.

1. Handle probe input captures, by adding input ports driven by a ref.resolve in the parent and recreate the probe by a ref.send of the input argument.
   For example,

// Before: 
    %w = firrtl.wire : !firrtl.uint<1>
    %r = firrtl.ref.send %w : !firrtl.uint<1>
    firrtl.layerblock @A {
      firrtl.ref.resolve %r : !firrtl.probe<uint<1>>
    }
  
// After:
  firrtl.module private @ProbeCapture_A(in %_0: !firrtl.uint<1>) {
      %0 = firrtl.ref.send %_0 : !firrtl.uint<1>
      %1 = firrtl.ref.resolve %0 : !firrtl.probe<uint<1>>
    }
    firrtl.module @ProbeCapture() {
      %w = firrtl.wire : !firrtl.uint<1>
      %0 = firrtl.ref.send %w : !firrtl.uint<1>
      %1 = firrtl.ref.resolve %0 : !firrtl.probe<uint<1>>
      firrtl.instance @ProbeCapture_A(in %1: !firrtl.uint<1>)
    }

2. Handle probe output escape by adding probe type output ports.

 // Before:
%dest_ref = firrtl.wire : !firrtl.probe<uint<1>, @A>
firrtl.layerblock @A {
  %src_ref = firrtl.wire : !firrtl.probe<uint<1>, @A>
  firrtl.ref.define %dest_ref, %src_ref : !firrtl.probe<uint<1>, @A>
}

// After:
firrtl.module private @Layer_A(out %p: !firrtl.probe<uint<1>>) {  
  %src_ref = firrtl.wire : !firrtl.probe<uint<1>>
  firrtl.ref.define %p, %src_ref : !firrtl.probe<uint<1>>
}
firrtl.module @Parent() {
  %dest_ref = firrtl.wire : !firrtl.probe<uint<1>>
  %p = firrtl.instance @Layer_A(out %p: !firrtl.probe<uint<1>>)
  firrtl.ref.define %dest_ref, %p : !firrtl.probe<uint<1>>
}

AI-assisted-by: Claude Sonnet 4.5

[fabianschuiki]

Results of circt-tests run for 895f895 compared to results for 7763950: no change to test results.