Handle mapped program memory segment aliasing properly, on WCH RISC-V targets

- Added `program_segment_key` target config param, to allow the user to specify the desired program memory segment
- Added the ability to resolve the currently aliased segment, by means of probing the mapped segment
- Added program counter transformation, when the mapped segment is aliasing a foreign segment
- Other bites of tidying

src/Targets/RiscV/RiscV.cpp

@@ -9,6 +9,8 @@
 #include "src/Services/StringService.hpp"
 #include "src/Logger/Logger.hpp"
 
+#include "Exceptions/IllegalMemoryAccess.hpp"
+
 #include "src/Exceptions/Exception.hpp"
 #include "src/Exceptions/InvalidConfig.hpp"
 #include "src/TargetController/Exceptions/TargetOperationFailure.hpp"
@@ -307,6 +309,20 @@ namespace Targets::RiscV
         return this->programmingMode;
     }
 
+    bool RiscV::probeMemory(
+        const TargetAddressSpaceDescriptor& addressSpaceDescriptor,
+        const TargetMemorySegmentDescriptor& memorySegmentDescriptor,
+        Targets::TargetMemoryAddress address
+    ) {
+        try {
+            this->riscVDebugInterface->readMemory(addressSpaceDescriptor, memorySegmentDescriptor, address, 4, {});
+            return true;
+
+        } catch (const Exceptions::IllegalMemoryAccess&) {
+            return false;
+        }
+    }
+
     void RiscV::applyDebugInterfaceAccessRestrictions(TargetAddressSpaceDescriptor& addressSpaceDescriptor) {
         for (auto& [segmentKey, segmentDescriptor] : addressSpaceDescriptor.segmentDescriptorsByKey) {
             this->riscVDebugInterface->applyAccessRestrictions(segmentDescriptor);