Support different memory address representations for variables

(based on https://github.com/eclipse-cdt-cloud/vscode-memory-inspector/pull/96#discussion_r1523567127)

When querying the memory address for a variable, we currently only support hexadecimal addresses in our default implementation of the C Tracker. However, the [ReadMemoryResponse](https://microsoft.github.io/debug-adapter-protocol/specification#Requests_ReadMemory) and [DisassembledInstruction](https://microsoft.github.io/debug-adapter-protocol/specification#Types_DisassembledInstruction) also support the decimal format as an argument. We should at least think about supporting those two formats and may consider supporting other formats such as octal or binary as well. In those cases, we need to consider whether we do want to convert them to hex or decimal for further processing as they are the only formats mentioned explicitly by the DAP.