[GR-47365] Integrate proxy registration to the reflection config

[graalvmbot]

This PR includes the registration of proxy classes for runtime instantiation into the reflection configuration. This allows the registration of reflection queries on proxy classes, which was not possible until now.
The existing handling of proxy configuration files is still here to handle existing files, but the agent is modified to use the new behavior.

The new format to specify proxy classes is the following:

{
  "type": { "proxy": [
    "InterfaceName1",
    "InterfaceName2",
    ...
  ]},
  ... (member registrations)
}

Here's a summary of the main changes:

• The agent (BreakpointInterceptor) is modified to consistently handle proxy classes, instead of the case-by-case approach used until now. Proxies are encoded as an array of interfaces in the trace files;
• ProxyConfigurationTypeDescriptor enables handling of proxy classes in configuration code;
• Types are now passed as ConfigurationTypeDescriptor from parsing onwards, notably in ConfigurationType;
• ReflectionRegistry now takes a ProxyRegistry to register proxy classes.